If a stone is dropped from a height of Variable  isn't defined feet, its height after t seconds is given by . Find the stone's velocity at time

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A.  ft/s
B. ? ft/s
C. ? ft/s
D. ? ft/s
E. ? ft/s

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Answer: D

Mathematics

If a projectile is fired with an initial speed of ft/s at an angle ? above the horizontal, then its position after t seconds is given by the parametric equations x =(cos?)t and y = (sin?)t-16 where x and y are measured in feet.

Suppose a gun fires a bullet into the air with an initial speed of 1024 ft/s at an angle of 30° to the horizontal. After how many seconds will the bullet hit the ground? (a) 36 s (b) 64 s (c) 16 s (e) none of these

Find the point(s) at which the given function equals its average value on the given interval.f(x) = 3 - x2; [-5, 4]

A. ±
B. ±
C. ±3
D.

Perform the indicated operations and simplify the result. Leave the answer in factored form. + 

A.  
B.
C. 1
D.  

Subtract the polynomials. Assume all variable exponents represent whole numbers.(4y2n + 4yn - 1) - (5y2n + 6yn + 4)

A. -y2n - 2yn - 5 B. -y2n + 2yn - 5 C. -y2n - 2yn + 3 D. y2n - 2yn - 5