Homework Section 6.2 1) Find the critical value, to for c = 0.99 and n = 10. 2) Find the critical value, to, for c = 0.95 and n = 16. 3) Find the margin of error E for c = 0.99, n = 18 and s = 2.6. 4) A sample of 25 IQ scores has a mean score of 105.8 and a standard deviation of 15. Construct a 90% confidence interval for the population mean. Assume that IQ scores are normally distributed. 5) Construct a 95% confidence interval for the population mean. Assume the population has a normal distribution. A sample of 20 college students had mean annual earnings of $ 3120 with a standard deviation of $ 677