Answer:
D
Step-by-step explanation:

Therefore, the correct answer is D. Hope this helps!
Answer:
120
Step-by-step explanation:
There are 5 ways to choose the first position, 4 ways to choose the second and so on until we get only 1 way to choose the last position, therefore the answer is 5! = 5 * 4 * 3 * 2 * 1 = 120 ways.
36x^2-49
this closely matches the binomial formula of (a+b)*(a-b)=a^2-b^2
so we know:
a^2=36x^2
a=6x
b^2=49
b=7
so (a+b)*(a-b)=(6x+7)*(6x-7)=36x^2-49