Nathan has just bought a new car. he models the value, v, in dollars, of the car after t years as v(t) = 21,000(0.861)t. based on this model, by what percent does the value of nathan's car decrease each year?

13.9%

Step-by-step explanation:

The value of car is modeled as:

Here we can see that, each year Nathan has considered 0.861 of the previous year value or we can say that Nathan has considered 86.1% of the previous year value. So,

We subtract the percentage value considered from 100 to find out the percentage decrease in the value of the car.

The value of new car is decreasing by 13.9% each year.  

b

step-by-step explanation:

ratio is 2 : 9

the answer is three

13.5 : 3