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4) a) The mean amount of time a random sample of 52 Americans 16 and older spent watching television each day is 2.8 hours and it is known the population standard deviation is 0.65 hour. Construct a 98% confidence interval for the population mean amount of time Americans 16 or older watch television. Interpret your result. b) If in the above scenario, a claim is made that the population mean number of hours Americans age 16 and older watch television is 2.5 hours per day. Would this claim be valid or invalid, based on the results in part (a)? 5) a) Jimmy sells custom wood signs on Etsy. Over the past year the mean monthly income from the business was $1326 with a standard deviation of $197. He expects next year's sales to be similar. Construct a 95% confidence interval for next year's mean monthly income. Interpret your result. b) If in the above scenario, a claim is made that the population mean monthly income is $1400. Would this claim be valid or invalid, based on the results in part (a)? MacBook Pro