9. ACT scores are normally distributed around a mean of 22, with a standard deviation of 4. What proportion of the the population scored higher than 29? 10. Random variable X has a sample mean household income level = $4,000. It is normally distributed with sigma = $14,000. What is the required sample size required to get the margin of error of a 95% confidence interval to equal $500? 11. Nestor Milk Powder is sold in packets with an advertised mean weight of 1.5kg. The standard deviation is known to be 184 grams. A consumer group wishes to check the accuracy of the advertised mean and takes a sample of 52 packets finding an average weight of 1.49kgs. What is the set of hypotheses that should be use to test the accuracy of advertised weight? 12. Enough with the multiple choice questions