Keep trying until you find the correct answer.

1. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

2. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

3. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

4. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

5. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

6. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

7. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

8. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

9. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
   

   1.   ?    V₁
   2.   ?    V₂

10. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

11. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

12. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

13. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

14. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

15. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

16. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the shore?
    

    1.   ?    V₁
    2.   ?    V₂

17. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

18. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

19. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

20. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

21. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

22. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

23. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

24. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

25. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

26. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

27. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

28. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

29. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

30. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

31. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

32. A boat is crossing a river in the diagram below. Which velocity is measured by the person on the boat?
    

    1.   ?    V₁
    2.   ?    V₂

33. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

34. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

35. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

36. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

37. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

38. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

39. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

40. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

41. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

42. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

43. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

44. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

45. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

46. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

47. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

48. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the shore?
    

    1.   ?    D₁
    2.   ?    D₂

49. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

50. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

51. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

52. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

53. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

54. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

55. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

56. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

57. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

58. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

59. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

60. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

61. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

62. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

63. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

64. A boat is crossing a river in the diagram below. Which distance is travelled by the boat as measured by the person on the boat?
    

    1.   ?    D₁
    2.   ?    D₂

65. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

66. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

67. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

68. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

69. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

70. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

71. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

72. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

73. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

74. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

75. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

76. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

77. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

78. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

79. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

80. A boat is crossing a river in the diagram below. Does the person on the boat aim the boat straight across the river or upriver?
    

    1.   ?    straight across
    2.   ?    upriver

81. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

82. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

83. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

84. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

85. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

86. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

87. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

88. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

89. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

90. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

91. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

92. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

93. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

94. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

95. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

96. A boat is crossing a river in the diagram below. Does the boat land straight across the river or downriver?
    

    1.   ?    downriver
    2.   ?    straight across

97. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
    

    1.   ?    D_river
    2.   ?    zero (straight across)

98. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
    

    1.   ?    D_river
    2.   ?    zero (straight across)

99. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
    

    1.   ?    D_river
    2.   ?    zero (straight across)

100. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

101. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

102. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

103. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

104. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

105. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

106. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

107. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

108. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

109. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

110. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

111. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

112. A boat is crossing a river in the diagram below. How far downriver does the boat land on the far shore?
     

     1.   ?    D_river
     2.   ?    zero (straight across)

113. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

114. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

115. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

116. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

117. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

118. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

119. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

120. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

121. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

122. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

123. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

124. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

125. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

126. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

127. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

128. A boat is crossing a river in the diagram below. Does the boat take the shortest possible time to get across?
     

     1.   ?    Yes
     2.   ?    No

129. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

130. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

131. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

132. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

133. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

134. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

135. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

136. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

137. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

138. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

139. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

140. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

141. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

142. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

143. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

144. A boat is crossing a river in the diagram below. Which equation matches the diagram?
     

     1.   ?    D₁ = D₂ + D_river
     2.   ?    D₂ = D₁ + D_river

145. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

146. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

147. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

148. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

149. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

150. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

151. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

152. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

153. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

154. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

155. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

156. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

157. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

158. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

159. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t

160. A boat is crossing a river in the diagram below. What is the width W of the river?
     

     1.   ?    W = D₁t
     2.   ?    W = D₂t