Please answer the following short answer questions. Be as complete and concise as possible.

Use this information to answer questions 1 through 3: Jon has a weekly budget of $20, which he likes to spend on bagels and cups of tea. The price of a bagel is $4 each and the price of a cup of tea is $2 each.

1. What is the maximum number of bagels he could buy in a week?
2. What is the maximum number of cups of tea he could buy in a week?
3. What is Jon's opportunity cost of purchasing a bagel?
4. You are drinking bottles of water on a very hot day. Use the law of diminishing marginal utility to explain why you would eventually stop drinking water.
5. How does the essay and video clip "I, Pencil" support Adam Smith's concept of The Invisible Hand?