If a is a rational number and b is a rational number, why could c be an irrational number?

What is the compound interest in a three-year, $100,000 loan at a 10 percent annual interest rate a) 10.00 b) 21.00 c) 33.10 d) 46.41

Arestaurant offers a $12 dinner special that has 5 choices for an appetizer, 12 choices for an entrée, and 4 choices for a dessert. how many different meals are available when you select an appetizer, an entrée, and a dessert? a meal can be chosen in nothing ways. (type a whole number.)

Two angles are complementary. the larger angle is 36 more than the smaller angle. what is the measure of the larger angle?