1. rational 2. irrational 3. irrational 4. rational
Step-by-step explanation:
this picture will help
you
1.) You have 12 toppings. You choose one topping--that leaves you with 11 toppings. You choose another--that leaves 10. 12×11×10 = 1,320.
Multiply 1,320 topping choices by 6 cheeses to get 7,920 total combinations.
2.) (Though I'm less sure of these)
CDs: 6×5×4×3×2 = 720
Cassettes: 5×4 = 20
DVDs: 8×7×6×5 = 1680
