In order to find the concentration after 11 minutes, let's use the value of t = 11 in the function C(t) and then calculate its value:
[tex]\begin{gathered} C(t)=0.04(1-e^{-0.2t}) \\ C(11)=0.04(1-e^{-2.2}_{}) \\ C(11)=0.04(1-0.1108) \\ C(11)=0.04\cdot0.8892 \\ C(11)=0.035568 \end{gathered}[/tex]
Rounding to three decimal places, we have a concentration of 0.036.
