A clerk in the U.S. store often encounters the problem of given change for a purchase because customers usually don't want to receive a lot of coins: 1c, 5c, 10c, 25c. What is an optimal solution to minimize the number of coins for a change? 1. Develop an iterative greedy algorithm to have the minimum number of coins for a change x cents. 2. The coins consist of U.S. coins which are available. The owed amount is 36 cents. What is an optimal solution? 3. Suppose that 12-cent coin with the U.S. coins is available. The owed amount is 16 cents. What is an optimal solution