Aball is thrown upward from the top of a building. the function below shows the height of the ball in relation to sea level, f(t), in feet, at different times, t, in seconds:
f(t) = −16t2 + 48t + 100
the average rate of change of f(t) from t = 3 seconds to t = 5 seconds is per second.

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?

John kept track of how many baskets were made in a basketball game. after 4 minutes, 5 baskets were made. how many baskets were made between 9 and 10 minutes? a. 0 b. 1 c. 2 d. 3

For each phone call robert makes,he pays $0.10 for the first minute and $0.05 for each additional minute. what is the cost for two 5 minute calls ? a $0.60b $0.30c $0.15d $0.45 show work.