In this problem the expression that represente the paint in terms of time is:
[tex]p(t)=6t[/tex]and the area is represent as:
[tex]A(p)=\pi p^2[/tex]Part A: So to have the area in terms of p we can replace the first equation in the secon one so wi will get:
[tex]\begin{gathered} A(t)=\pi(6t)^2 \\ A(t)=36\pi t^2 \end{gathered}[/tex]Part B: now we can replace the 8 minutes in the equation so we get:
[tex]\begin{gathered} A(8)=36\cdot3.14\cdot8^2 \\ A(8)=7234.56 \end{gathered}[/tex]