From my calculus class. Please see Q2 - 23. Thank you very much for your help.

According the laws of physics when a rock is tossed up in the air on earth it goes up and comes down! The height of the rock at time t seconds can be modelled by: sit} = -15t1 + 1:9 t + ha \f2. Suppose a rock is tossed in the air from a height of 20 (units) with an initial velocity of 80 (units) .20. Use S"(t) to find: 5"(3) = S"(0) = S" (1) = _ 21. Solve S"(t) = 0. 22. Find S"(t) = 23. What does S'"(t) represent? Think about driving a car