The formula for exponential decay is

where a is the initial value (28750)
r is the rate of decrease (0.12)
x is the time, in this case in years (6 . 2018-2012 = 6 years)

<span>y </span>≈ <span>13351.62</span>
I can't tell if that is a question but I will answer it anyway:
An exterior of a shape is the lengths and angles outside of the shape.
An interior are the lengths and angles inside a shape.
Hope this helps.
The answer is 45 because you have to decide the number by what you just said
Answer:
7 million is the answer to this question