Question

Please circle answers

1. A company that produces cell phones has a cost function of C(x)=3x^2−1500x+39900 where C is cost in dollars and x is number of cell phones produced (in thousands). How many units of cell phones minimizes this cost function?

2. A ball is thrown into the air and its position is given by h(t)=−4.9t^2+70t+5 where tt is measured in seconds and h(t) is measured in meters above the ground. Find the height at which the ball stops ascending. How long after it is thrown does this happen?

1. Time at which ball stops ascending is (in seconds.)
2. Height at which ball stops ascending is

Answer 1