You have a Ferris wheel that only contains 10 carts total. Each cart can only hold 2 people. For every time a new cart cycles around, it takes 1 minute for that new cart to touch the ground. So in essence, it takes 10 min for a full revolution. The Ferris wheel only operates for 30 minutes, no less and no more. What is the max number of people you can seat before your shift is over. Hint: You cannot leave people on the Ferris cart before your shift ends.