At what angle with respect to the vertical must a scuba diver look in order to see her friend standing on the very distant shore? Take the index of refraction of the water to be n = 1.33.

The uniform slender bar rests on a smooth horizon- tal surface when a force f is applied normal to the bar at point a. point a is observed to have an initial acceleration aa of 20 m/s2, and the bar has a corre- sponding angular acceleration of 18 rad /s2. deter- mine the distance b.