Area of Quadrilateral by Heron's Formula

Q.

A field is in the shape of an isosceles trapezium with parallel sides measuring $\text{20 cm and 8 cm}$ and its non-parallel sides measuring $\text{10 cm}$. Find its area.

1. 84 ${cm}^2$
2. 112 ${cm}^2$
3. 101 ${cm}^2$
4. 96 ${cm}^2$

Q. If the area of an equilateral triangle is $16\sqrt{3}{\text{cm}}^2$, then the perimeter of the triangle is