I need the answer for question b.

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 $

Avegetable garden and a surrounding path are shaped like a square together are 12 ft wide. the path is 1 feet wide. if one bag of gravel covers 8 square feet, how manu bags are needed to cover the path? round your answers to the nearest tenth.

The axis of symmetry for the graph of the function f(x)=1/4^2+bx +10 is x=6. what is the value of b?