A ball is thrown into the air with an upward velocity of 28 ft/s. Its height (h) in feet after t seconds is given by the formula h=-16t^2+28t+7. How long does it take the ball to reach its maximum height? What is the balls maximum height? Round to the nearest hundredth, if necessary.
A. Reaches a maximum height of 7 feet after 1.75 seconds
B. Reaches a maximum height of 43.75 feet after 0.88 seconds
C. Reaches a maximum height of 17.5 feet after 0.88 seconds
D. Reaches a maximum height of 19.25 feet after 0.88 seconds

Question

A ball is thrown into the air with an upward velocity of 28 ft/s. Its height (h) in feet after t seconds is given by the formula h=-16t^2+28t+7. How long does it take the ball to reach its maximum height? What is the balls maximum height? Round to the nearest hundredth, if necessary.
A. Reaches a maximum height of 7 feet after 1.75 seconds 
B.  Reaches a maximum height of 43.75 feet after 0.88 seconds 
C. Reaches a maximum height of 17.5 feet after 0.88 seconds 
D. Reaches a maximum height of 19.25 feet after 0.88 seconds

anonymous · Answer

Really need help guys!

anonymous · Answer

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anonymous · Answer

what is the derivative of the formula?

anonymous · Answer

I don't know. Just walk me threw it.

anonymous · Answer

You don't know how to do derivatives?

anonymous · Answer

No aha. I never paid attention in school and got expelled so I have no clue. Just doing it one day at a time.