a) A researcher wants to test the claim that all convicted burglars spend a mean time of 18.7 months in jail. She takes a random sample of 11 such cases from court files and finds a sample mean jail time of 21.2 months with a standard deviation of 4.4 months. Test the claim that ? = 18.7 months at the 0.01 significance level.

B) Use a 0.005significance level to test the claim that ? > 80 pounds. Thesample statistics are: n = 44, x?= 81 pounds. Assume that ?= 12.5

C) Use a 0.01significance level to test the claim that ? ? 83 liters. The sample statistics are: n = 55andx?= 85 liters. Assume that ?= 7.8