Who invited math?? Please answer

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

How do i make someone brainliest? (if you answer me, i might be able to make you brainliest! )

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base