1. What drag force acts on a 76-cm-diameter sphere towed 2 m below the surface of water at 20 m=s?
2. A 2.2-m-long hydrofoil with chord length 50 cm operates 40 cm below the water's surface with an angle of attack of 4-. For a speed of 15 m=s determine the drag and lift and decide if cavitation exists on the hydrofoil.