Aracing car driver makes a pit stop at the beginning of a lap. the time, t, in seconds that it takes the driver to complete the lap including the pit stop, can be modeled by this equation. the variable, r, is the driver's average speed in miles per hour after the pit stop. what is the horizontal asymptote of the function? (equation: t=(12r+9000)/(r) multiple choice answers a. t=12 b. t=0 c. r=9000 d. r=0