Is this function linear or nonlinear?

Franco wants to double the volume of the cone. what should he do?

Elena and her husband marc both drive to work. elena's car has a current mileage (total distance driven) of 15,000 and she drives 23,000 miles more each year. marc's car has a current mileage of 46,000 and he drives 9,000 miles more each year. will the mileages for the two cars ever be equal? explain.

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c