Can you help? I have been stuck on this because I don't get it may someone please help me? Here it is: ​

The circumference of a redwood tree trunk is 20π ft, and it is 100 ft tall. what is the approximate volume of the redwood tree trunk? 1,000π ft3 10,000π ft3 4,000π ft3 40,000π ft3

Select the margin of error that corresponds to the sample mean that corresponds to each population: a population mean of 360, a standard deviation of 4, and a margin of error of 2.5%

Find an bif a = {3, 6, 9, 12) and b = {2, 4, 6, 8, 10).