In order to calculate the area after 12 years, let's use the following exponential model:
[tex]A=A_0\cdot(1+r)^t[/tex]Where A is the area after t years, A0 is the initial area and r is the rate of increase or decrease.
So, for A0 = 4000, r = -0.055 and t = 12, we have:
[tex]\begin{gathered} A=4000\cdot(1-0.055)^{12} \\ A=4000\cdot0.945^{12} \\ A=4000\cdot0.50720287 \\ A=2028.8 \end{gathered}[/tex]Rounding to the nearest km², the area is 2029 km².