F(t) can be factored to find the zeros.
.. f(t) = -5(t -5)(t +2) . . . . f(t) = 0 for t=-2, t=5
The object hits the ground after 5 seconds.
1.)subtract 600 from 750 in order to simplify
2.)divide by 15 on both sides to get y alone. Doing this cancels the 15 on the y and makes the right side equal 10
3.)y=10
Here is your answer
A. 1,3,5,7,9,11,.....
REASON :
In an AP their is a common difference between two consecutive terms.
i.e. t2-t1=t3-t2=t4-t3=....= constant
The option A satisfies above condition.
HOPE IT IS USEFUL
Answer is 8 because you divide 30 by 5 then you get 6 and when you get 6 you add 2 and the answer is 8