Can someone me answer b and c? i'm really stuck on those 2

a. pick a reasonable amount of time in which the three friends can paint the room together. also pick a reasonable amount of time in which john can paint the room alone and a reasonable amount of time in which rick can paint the room alone. 8 hours- 3 friends, 12 hours- john, 12 hours- rick

b. what is the hourly rate for john, rick, and molli (when working together)? use rooms per hour as the unit for your rates.

c. what is the hourly rate for john? what is the hourly rate for rick? refer to the amount of time you determined in which john and rick can paint the room alone. use rooms per hour as the unit for your rates.