1. If the area of an equilateral triangle is 36√3 cm², find its perimeter (in cm).   Hint Hint       2. Find the area (in cm²) of a triangle with base 12 cm and height 7 cm.   Hint       3. The lengths of the sides of a triangle are in the ratio 3 : 4 : 5 and its perimeter is 72 cm. Find the area (in cm²) of the triangle.   Hint       4. The difference between the sides of a right-angled triangle containing the right angle is 7 cm and its area is 60 cm². Calculate the perimeter (in cm) of the triangle.   Hint       5. Calculate the height (in cm to the nearest integer) of an equilateral triangle whose area is 36.95 cm².   Hint       6. Calculate the height (in cm) of a triangle whose base is 24 cm and area is 180 cm².   Hint       7. Calculate the area (in cm² upto 1 decimal place) of an equilateral triangle of side 10 cm.   Hint