Keep in mind that the graph counts in twos.
The factored form of the polynomial deals with the zeros in the graph. Identify the zeros in the graph:
Zeros at:
x = -4, (-4,0)
x = 4, (4,0)
Both values must be inputted into the answer and result in an output of 0, so the answer will be
C. (x+4)(x-4).
Proof:
x = 4:

x = -4

We know the total distance and individual times, so we can sum and equate total distance.
Let
E=speed heading east
E+45=speed heading south
then
4(E+45)+6E=3370 miles
Solve for E:
4E+180+6E=3370
10E=3370-180=3190 mph
E=319 mph.
Leap years have 366 days, and there are 8 pints per gallon. So we divide the 366 days by the 8 pints per 1 gallon. We end up getting:
45.75 gallons in 1 leap year.
Given :

We know the identity
We use this property to simplify the left hand side
So 

we know ,
when
then

For 

Add
on both sides

Finally we add 2npi for general solution
So options C and D are correct