1. How many 10-bit strings are there which contain exactly six O's and whose first bit is a 1. 2. Ten members of a club are lining up in a row for a photograph. The club has one president and one vice-president. How many ways are there for the club members to line up in which the president is not next to the vice-president? 3. Twenty different comic books will be distributed to four kids. How many ways are there to distribute the comic books if they are divided evenly so that five go to each kid