31.The area of a triangle can be determined using Heron's formula, which requires the side lengths of the triangle.
Heron's formula is A=√s(s-a)(s-b)(s-c). In the formula A is the area; a,b and c are the side lengths; and s is half the perimeter or a+b+c.
Determine the area of each triangle with the following side lengths.
Express each area to the nearest tenth of a square centimetre.