In this question they've given us the formula and they just want us to plug in the numbers and get the value.
P is the original value, P=$600
r is the depreciation rate, r=10%=0.1
t is the time in years, t=2
[tex]A = P(1-r)^t = 600(1 - 0.1)^2 = 600 \cdot .9^2 = 486[/tex]
Answer: $486
