People have been very patient with all your questions but you are monopolising the site to an unacceptable extent.
You can continue to ask questions on a single posting and not start a new one each time. Your posts have taken up what amounts to a whole page to the detriment of others and their questions.
Please use your existing post to continue your discussions.
Area = pi x r x r
so 200 = 3.142 x r x r
200 divided by 3.142 = r x r
63.65 = r x r
then you need the square root of 63.65 for the radius
this is 7.98
now double this to get the diameter!
thank yoyu sooo much like i am very great ful for you trying to help me but maybe circles and radiouses i will never get how to do circles and cicumfrances