A particle moves along a coordinate axis so that the position at time t is given bys(t) = 7 cos t + 4t for 0 t 2. At what times is the particle at rest?

t = ,

A series of ocean waves have the form f(x) = 13 sin(23t) + 19 feet, where the ocean floor is at f(x) = 0 feet. What is the highest a wave reaches above the ocean floor? What is the period of the waves?