I don't know how to do this, please help

If ac = 12 and ab=7 is it possible that bc =10

To complete your spring schedule, you must add calculus and physics. at 9: 30, there are three calculus sections and two physics sections; while at 11: 30, there are two calculus sections and three physics sections. how many ways can you complete your schedule if your only open periods are 9: 30 and 11: 30?

If you could answer these your a life saver