PLEASE HELP!!!! HAVEN'T DONE CALCULUS AND DERIVATIVES IN ABOUT 20 YEARS....

Details:
Interest Rate: 6%, Inflation Rate: 2%

Honda Civic - Gas: Price - $16, 710, Fuel Consumption: 28 mpg
Toyota Prius: Price - $23,370, Fuel Consumption: 44 mpg
Honda Civic - Hybrid: Price - $24,150, Fuel Consumption: 37 mpg

#1 - At what price per gallon of gasoline would it be more economical to purchase and operate a hybrid car if we drove an average of 15,000 miles per year

#2 - At what price would a hybrid need to be sold, above which it would remain uneconomical to purchase one if gasoline prices were at $3.50 per gallon (again, assume 15,000 miles average driving per year)