answers for a-f

An object thrown vertically upward from the surface of a celestial body at a velocity of 21 m/s reaches a height of s = - 0.7t2 + 21t meters in t seconds. a. Determine the velocity v of the object after t seconds b. When does the object reach its highest point? c. What is the height of the object at the highest point? d. When does the object strike the ground? e. With what velocity does the object strike the ground? f. On what intervals is the speed increasing? a. The object's velocity after t seconds is v(t) =