Bill is ten years old. One day his friend Tom says to him, "I am going to have a birthday party on Sunday evening. Bill, can you come to my party?" "I'll be glad to," answers Bill. Before Bill goes to the party on Sunday afternoon, his mother says to him, "Now, Bill, don't forget  to be polite . Don't ask for food until  someone gives it to you.""All right, Mum." Bill answers, and he goes to Tom's house on his new bike. There are a lot of children at the party. They play for an hour. Then Tom's mother gives them some food. But she forgets to give Bill any. He waits politely for ten minutes and then holds his plate up  in the air and says loudly , "Does anyone want a nice and clean plate?" How old is Bill?
Eight. Ten. Twenty. Eleven.