The arc length of a sector created by a 90 degrees angle is 2 pi cm. What is the circumference of the entire circle? Express the answer in terms of Pi.

Recall the formula StartFraction Arc length over Circumference EndFraction = StartFraction n degrees over 360 degrees EndFraction.
StartFraction pi over 4 EndFraction centimeters
StartFraction pi over 2 EndFraction centimeters
6 pi centimeters

(b) suppose that consolidated power decides to use a level of significance of α = .05, and suppose a random sample of 100 temperature readings is obtained. if the sample mean of the 100 temperature readings is x⎯⎯ = 60.990, test h0 versus ha and determine whether the power plant should be shut down and the cooling system repaired. perform the hypothesis test by using a critical value and a p-value. assume σ = 5. (round your z to 2 decimal places and p-value to 4 decimal places.)