Given : A lens face with a radius of 15 mm
We need to find the area
So, the lens has the shape of the semi sphere
Consider it a circle
The radius of the circle = r = 15 mm
The area of the circle =
![\pi\cdot r^2](https://img.qammunity.org/2023/formulas/mathematics/college/wzet5ba4epys3d01b741jttxx3lxgbk3no.png)
So, the area of the lens =
![\begin{gathered} \pi\cdot r^2 \\ \\ =3.14\cdot15^2=706.5\operatorname{mm} \end{gathered}]()
So, the area of the lens = 706.5 mm^2