In order to find each one, you use the formula A=pi R², meaning you put the radius to the power of two(multiply it by itself) and then multiply that by pi. ex: 7.4×7.4= 54.76,
next 54.76×3.14=171.9, which is your answer. If it gives you the diameter of the circle, divide that by two to get the radius, and follow the steps from before. Ex: 2.24÷2=1.12, next 1.12×1.12=1.2544, next 1.2544×3.14=3.9, the answer.