If f(x) = 2x2 − 30, find f(4) would you put the 4 in the f(x) place?

If f(x)=2x+2and g(x)=x^3, what is (g•f)(2)

Pls! does anybody know a shortcut for answering these types of questions in the future?

Steve had 48 chocolates but he decided to give 8 chocolats to each of his f coworkers. how many chocolates does steve have left