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5. The following data show the number of hours per day 12 adults spent in front of screens watching television-related content. Complete parts a and b below. 1.4 5.1 4.3 5.4 7.5 7.20 5.7 2.4 5.5 1.9 2.6 8.4 a. Construct a 90% confidence interval to estimate the average number of hours per day adults spend in front of screens watching television-related content. The 90% confidence interval to estimate the average number of hours per day adults spend in front of screens watching television-related content is from 3.64 hours to 6.06 hours. ( Round to two decimal places as needed.) b. What assumptions need to be made about this population? O A. The only assumption needed is that the population distribution is approximately normal. O B. The only assumption needed is that the population standard deviation is known. O C. The only assumption needed is that the population distribution is approximately uniform. O D. No assumptions are required