+109 A motorcycle is depreciating at 19% per year, every year. A student's $21,000 motorcycle depreciating at this rate can be modeled by the equation V(t) = 21,000(0.81)^t. What is an equivalent equation for this vehicle as a monthly depreciation and, using this equation, what is the motorcycle worth (rounded to the nearest ten dollar) 4 years after purchase?
a.)v(t)=21,000 (1.19)^-t, $10,470
b.)v(t)=21,000(0.8100)^12t, $19,580
c.) v(t)=21,000(0.9826)^12t, $9040
d.) v(t)=21,000(0.9826)^t, $9,040
