Water Is Flowing in a Drainage Channel of Rectangular Cross-Section

Multiple Choice

Water is flowing in a drainage channel of rectangular cross-section. At one point, the width of the channel is 12 m, the depth of water is 6.0 m, and the speed of the flow is 2.5 m/s. At a point downstream, the width has narrowed to 9.0 m, and the depth of water is 8.0 m. What is the speed of the flow at the second point?

A) 2.0 m/s
B) 2.5 m/s
C) 3.0 m/s
D) 3.5 m/s
E) 4.0 m/s