#1 I'd like to help, but I'm not sure what the notation (fog)'(3) means. Is the ' a prime, representing a derivative?

#2 Find F'(a):

Since F(x) = f(x^6), taking the derivative, we need to use chain rule:

F'(x) = f'(x^6)*6x^5

F'(a) = f'(a^6)*6a^5

Now, we know f'(a^{6})=10, a^{5}=10, so we get

F'(a) = {10}*6*{10} = 600