A pizza parlor offers three types of crust and peppers, onions, eggplants, olives, artichokes, as toppings for the plain cheese base. We assume that...

A pizza parlor offers three types of crust and peppers, onions, eggplants, olives, artichokes, as toppings for the plain cheese base. We assume that duplicate toppings are not allowed.

(a) How many different pizzas can be made?

(b) How many pizzas are there with exactly three toppings?

(c) How many pizzas are there with at least 2 toppings?