A current in a river flows downstream at a speed of 2 m/s. A swimmer can swin with a speed of 0.5 m/s with respect to the water. The swimmer heads directly across the stream, and crosses the stream in a time of 30 seconds. How wide is the stream?

According to the tide table below what time of day will the highest tide occur?

Light traveling in water, nwater = 1.33, strikes a plastic block at an angle of incidence of 51.4°; part of the beam is reflected and part is refracted. if the index of refraction of the plastic is 2.0, what is the angle made by the reflected and refracted beams?

Atank has a shape of a cone with a radius at the top of 2 m and a height of 5 m. the tank also has a 1 m spout at the top of the tank. the tank is filled with water up to a height of 2 m. find the work needed to pump all the water out the top of the spout. (use 9.8 m/s2 for g and the fact that the density of water is 1000 kg/m3.)