For the given problem, fill-in the answer with the correct n…
For the given problem, fill-in the answer with the correct number value. The Rufus Cafe has a special lunch menu in which the diner chooses a soup or salad, a main course, and a dessert. There are `S1` choices of soups, `S2` choices of salads, `M` choices of the main courses, and `D` choices of desserts. Determine how many different three-course meals diners can order for lunch.