A retailer returned 2,124 defective items to the manufacturer and received a credit for the retail price of $0.66 or 66 2
3¢ per item less a discount of
7
9 of the retail price. What was the amount of the credit received by the retailer?

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables