1. There are 21 cakes. Each cake is cut into 10 parts. Each part is further cut into 2 pieces. How many cake pieces are there in all?   2. The Professors at the State University drank 128 cups of tea yesterday. They drank 75 cups in the morning and 29 in the afternoon. How many did they drink in the evening?   3. Peter has a collection of 97 books. He donated 15 books last year and 26 books this year. How many books does he still have?   4. A school has 5 dining halls. Each dining hall has37 tables. If there are four children to each table, how many children stay for lunch?   5. Last month, Jack worked for 196 hours, Greg worked for 122 hours, and Edward worked 37 hours more than Jack. How many hours did they work altogether?