We apply the fundamental counting principle which says that if there are \(n\) ways of doing something, and \(m\) ways of doing another thing after that, then there are \(n∗m\) ways to perform both of these actions.

There are \(4\) ways of choosing an Entree

There are \(5\) ways of choosing a Dessert

There are \(6C2\) ways of choosing an Appetizer

Total number of meal combinations available \(= 4 * 5 * 6C2 = 4 * 5 * 6!/(6-2)! * 2! = 4 * 5 * 15 = 300\)