A normaLpopulationhaunean u = 40 and standard deviat on 0' = 9. (a) What proportion of the population is between 20 and 3|? (b) What is the probability that a randomly chosen value "I be between 35 and 45? The proportion of the population between 20 and 30 is D. The probability that a randomly chosen value will be between 35 and 45 is D. ull 'n Using the 11-84 calculator; nd the area under the standard normal curve that lies between the following z-values. Round the answers to four decimal places. 0:\" (a) Find the area under the standard normal curve that lies between 2: 1.71 and 2: 1.25. (b) Find the area under the standard normal curve that lies between 2: -0.29 and Z: 0.12. (c) Find the area under the standard normal curve that lies between 2 =1.56 and Z: 1.98. (d) Find the area under the standard normal curve that lies between 2: 2.17 and z=0.07. The area between z= 1.71 and z= 1.25 is E]. The area between 2: 0.29 and 2: 0.12 is D. The area between 2 = 1.56 and z= 1.98 is D . The area between z= 2.17 and z=0.07 is D. How many computers? In a simple random sample of 145 households, the sample mean number of personal computers was 1.81. Assume the population standard deviation is o= 0.69. (a) Construct a 99% condence interval for the mean number of personal computers. Round the answer to at least two decimal places. A 99% condence interval for the mean number of personal computers is E]