An object is dropped from a tower, 159 At above the ground. The object's height above ground t sec into the fall is s = 159 -1612 a. What is the object's velocity, speed, and acceleration at time t? b. About how long does it take the object to hit the ground? c. What is the object's velocity at the moment of impact? The object's velocity at time t is The object's speed at time t is |ft/sec. The object's acceleration at time t is |ft/sec (Simplify your answer.) It takes sec for the object to hit the ground. (Round to the nearest tenth.) The object's velocity at the moment of impact is |ft/sec. (Round to the nearest tenth.)