Aplumber finds that 4/5 of pipe joint compound is needed for each home. how many holes can be plumbed with 212 cans of compound?

Aye asap pls ! markin da brainiest too ! btw da step choices are all add, distribute, divide, n subtract

Scores on the cognitive scale of the bayley-scales of infant and toddler development range from 1 to 19, with a standard deviation of 3. calculate the margin of error in estimating the true mean cognitive scale score, with 99% confidence, if there are 12 infants and toddlers in a sample.

How is this equation completed? i cannot find any examples in the book.