1.) Abe can tow a truck in 40 min. If his son Dominic helps him, it takes them 15 minute. How long will it take Dominic to finish alone?

2.) Irish can do a job in 30 minutes. Sheena can do it in 40 minutes and Shine can do it in 60 minutes. How long will it take them if they work together?

3.) One pipe can fill a pool in 6 hours. The drain can empty the pool in 12 hours. With the pipe on and the drain open, how long would it take the pool to be filled?
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