Suppose that f(5) = 1, f'(5) = 7, g(5) = -5, and g'(5) = 4. Find the following values.
(a) (fg) '(5)
b) (f/g) '(5)
c) (g/f) '(5)
a) 39
b) -7/5
c) -7/39
d) 5/7