Simplify the expression and state any restrictions

How do you write 600 as a product of its prime factors (index! )

X^2/100+y^2/25=1 the length of the major axis is: a)5 b)10 c)20

If f(x)= x^2 - 4 and g(x)=x^2 + 2 x, (b). (f-g)(x) i think i know the 1st 2 steps: f(x)-g(x) x^2-4 - x^2+2x