I think the answer is 6530 because ask yourself, what amount is in the hundreds section, which is 526. the rule is : if your number is past 5 hundred twenty five you round up to the nearest tenth, which is 5hundred thirty. so your answer is 6,530. I hope I explained it to be understandable...
A. If you know the diameter, you can find the radius of a sphere by dividing the diameter in half. If you know the circumference, you can find the radius by dividing the circumference by 2 times pi
B. π × r2 × h
False, they are both quadrilaterals though.