A window repair specialist charges $220 for the first two hours of repair plus an hourly fee for each additional hour. The total cost for 5 hours of repair is $400. Which function f gives the total cost, in dollars, for x hours of repair, where x≥2?
f(x)=60x+100
f(x)=60x+220
f(x)=80x
f(x)=80x+220