Resposta:
[tex]\textsf{Leia abaixo}[/tex]
Explicação passo a passo:
[tex]\mathsf{r = \dfrac{D}{2}}[/tex]
[tex]\mathsf{r = \dfrac{7}{2}}[/tex]
[tex]\mathsf{r = 3,50\:cm}[/tex]
[tex]\mathsf{A = \pi .r^2}[/tex]
[tex]\mathsf{A = (3,14) .(3,50)^2}[/tex]
[tex]\boxed{\boxed{\mathsf{A = 38,47\:cm^2}}}[/tex]
