Can someone please help me solve these three problems:

1) Let f be the function defined by f(x) = 2x^4 + 5. Find f(a+h), f(2a-h).

2) Let f be the function defined by f(x) = -3x^2 – 3. Find f(1/2), f(-3/4).

3) Let f(x) = 3x – 4 and g(x) = (-1/3)x^2 – 4x. Find f+g, f-g, f/g, f∙g, f°g, g°f.

Thanks!!