A ball is thrown upward from the top of a 40 foot high building at a speed of 80 meter per second. The ball's height above ground can be modeled by the equation
H (t) = -16t? + 80t + 40
a. When does the ball reach the maximum height?

Ben is three times as old as samantha, who is two years older than half of michel's age. if michel is 12. how old is ben?

Suppose that the price p, in dollars, and the number of sales, x, of a certain item follow the equation 4 p plus 4 x plus 2 pxequals56. suppose also that p and x are both functions of time, measured in days. find the rate at which x is changing when xequals2, pequals6, and startfraction dp over dt endfraction equals1.5.

Erik buys 2.5 pounds of cashews. if each pound of cashews costs $7.70, how much will he pay for the cashews?