How many ways can 4 candy bars be chosen from a store that sells 30 candy bars (combination)

This is geometry. could anyone ? i can't fail this class. my grade is quite low already.

Someone . me. compound probability

The green family is a family of six people. they have used 4,885.78 gallons of water so far this month. they cannot exceed 9,750.05 gallons per month during drought season. write an inequality to show how much water just one member of the family can use for the remainder of the month, assuming each family member uses the same amount of water every month.