Dividing polynomials.. i need these 5 answered

Are carpet coast $15 per square metre. the total delivery charge is $21 peter buys n squared metres of carpet what is the expression which represents the total cost in $

The surface area of the triangular prism is .

15. jiovanni is looking in to two different companies that offer study guides for math exams.test prep 101 charges a $5 flat fee and an additional $0.25 per problem.math charges a $2 flat fee and an additional $0.50 per problem.how many prablems would make the costs of the two companies be equal? varibles: equations/eniqualities{ {