9. A company sells phone cases for $30 each. But if you buy at least 20 of them at once, they're just $27 each. And if you buy at least 50 at once, they're only $22 each. Write code that gets a number of cases bought at once from a user, and that prints the total cost of the purchase. 2 9. A company sells phone cases for $30 each. But if you buy at least 20 of them at once, they're just $27 each. And if you buy at least 50 at once, they're only $22 each. Write code that gets a number of cases bought at once from a user, and that prints the total cost of the purchase. 2