A swimmer can swim at a speed of 2.5 m/s in still water. When swimming across a river with a current, the swimmer must angle at 40° with respect to a line perpendicular to the shore to maintain a straight path as shown in the figure below. What is the swimmer's resultant speed with respect to the shore?

• A. 3.8 m/s
• B. 3.2 m/s
• C. 1.9 m/s
• D. 1.6 m/s

Answer: (C)