Modelling of Vertical motion

A dynamite blast blows a heavy rock straight up with a launch velocity of 160 ft/ sec. It reaches a height of S = [160x – 16x^2] feet after x sec. a) How high does the rock go? b) What are the velocity and speed of the rock when it is 256 ft above the ground on the way up? On the way down? c) What is the acceleration of the rock at any time t during its flight?
A dynamite blast blows a heavy rock straight up with a launch velocity of 160 ft/ sec. It reaches a height of S = 160 t – 16t2 feet after t sec. a) How high does the rock go? b) What are the velocity and speed of the rock when it is 256 ft above the ground on the way up? On the way down? c) What is the acceleration of the rock at any time t during its flight?