Has anyone done the Math integers unit test my little sister need help with it aka: needs the answers

Ateacher has $80 to buy workbooks. each work book cost $3. if she buys as many workbooks as possible, how much money does she have leftover? a) $2 b) $4 c) $6 d) $8

Select the margin of error that corresponds to the sample mean that corresponds to each population: a population mean of 25, a standard deviation of 2.5, and margin of error of 5%

Astore ordered 750 candles a total wholesale cost of $7910.20. the soy candles cosy $12.17 each and thespecialty candles cost $9.58each. how many of each were bought?