7. In lectures we learned that the 100(1 - a) percent confidence interval for a population proportion (p) is given by the formula pz*DC-D. In this formula, what is the value of z* for a 92 percent confidence interval? (a) 1.75 (b) 1.41 (c) 1.96 (d) 0.92 (c) 0.96 8. A confidence interval for a population proportion based on a sample of size n = 100 is (0.6968, 0.9032). What is the confidence level of this confidence interval? If none of the choices given below gives the exact answer, please pick the closest value.) (a) 99 percent confidence n = IGG (b) 95 percent confidence (c) 90 percent confidence G - 8 0 . 90 32 (d) 80 percent confidence (c) 85 percent confidence 9. A laboratory tested a random sample n - 20 chicken eggs and found that the mean amount of cholesterol was 237 milligrams with sample standard deviation 14 milligrams. Calculate the lower limit of the the 99% confidence interval for the truc mean cholesterol content of all such eggs. You may assume that all the conditions for the required calculations are met by the data. (If none of the choices given below gives the exact answer, please pick the closest valuc.) (a) 235 n = 20 (b) 233.9 mea = 237 (2) 234.6 SD = 14 ( d) 196.9 (c) 228 CJ = 2. 576 (