Which is not equivalent? d=rt dt=r d overt=r or d over r =t

Asmall foreign car gete 42 miles per gallon and user 35 gallons on a trip. gasoline costs $1.05 per gallon. what was the cost of gasoline per mile driver?

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Jacob signs up to work for 2 1/2 hours at the school carnival. if each work shift is 3/4 hour, how many shifts will jacob work? (i just want to double check : |, for anybody that responds! : )