Question

What is the area of this and why( how did you solve it)

Answer 1

The area of a circle is $\pi$ times the squared radius of the circle,

$A=\pi r^2$

You're given the diameter, which is twice the length of the radius,

$d=2r\implies r=\dfrac d2$

Plugging this into the area formula gives

$A=\pi\left(\dfrac d2\right)^2=\pi\dfrac{d^2}4$

The radius is 28 m, so the area is

$A=\pi\dfrac{(28\text{ m})^2}4=196\pi\approx615.75\text{ m}^2$