Which of the following is NOT an example of a contract?

1 An innkeeper agrees to provide a room to a guest and the guest agrees to pay the requested rate.

2 An innkeeper agrees to pay a snow plower in return for the plower agreeing to plow the hotel parking lot throughout the winter.

3 A bartender agrees to work for a restaurant, and the restaurant agrees to pay the bartender.

4 An innkeeper agrees to provide rooms for five homeless families on Christmas eve at no cost to those guests.

5 All of the above are examples of contracts.