1. A board game contains 52 total coins. There are 21 green coins, and 9 black coins. How many coins are there of other colors?   2. The doctors at Get-Well Hospital drank 57 cups of tea yesterday. They drank 17 cups in the morning and 11 in the afternoon. How many did they drink in the evening?   3. Ronnie borrowed 7 books from the school library. He returned 2 books yesterday and 3 books today. How many books does he still have?   4. Mrs. Nelson had a lovely 42-piece crockery set. Last evening, 4 cups and 4 saucers broke. How many pieces of crockery left?   5. Andy had half an hour to do his homework. He spent 5 minutes on English and 9 minutes on Science. How many minutes remain?