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An NRE graduate works for OFIC (Oman Food Investment Company) to test the content of vitamin C in the orange juice they are recently developing. He reported that true average content of vitamin C in the orange juice is between 11.7 to 12.3 ounces at 95% confidence level. Also, based on his sample, his report shows that the average content of vitamin C in the orange juice is 12 ounces. The report does not show the size of the sample used. Please find the sample size of the sample assuming the standard deviation of the population is 1.28