He monthly credit card debts for individual accounts are normally distributed with a standarddeviation of 61 dollars. A researcher wishes to estimate the mean monthly credit card debt for allindividual accounts. Find the sample size needed to assure with 95% confidence that the samplemean will not differ from the population mean by more than 2 units.

Circle a has a diameter of 7 inches, a circumference of 21.98 inches, and an area of 38.465 square inches. the diameter of circle b is 6 inches, the circumference is 18.84 inches, and the area is 28.26 square inches. part a: using the formula for circumference, solve for the value of pi for each circle. (4 points) part b: use the formula for area and solve for the value of pi for each circle. (4 points)