The manager of square mall wants to estimate the mean amount spent per shopping visit by customers. a sample of 20 customers reveals the following amounts spent. $48.16 $42.22 $46.82 $51.45 $23.78 $41.86 $54.86 37.92 52.64 48.59 50.82 46.94 61.83 61.69 49.17 61.46 51.35 52.68 58.84 43.88 (hint: use t-test) a. determine a 95% confidence interval. interpret the results b. would it be reasonable to conclude that the population mean is $50? what about $60?