A marketing researcher wants to estimate the mean amount spent per year ($) on a web site by membership member shoppers. Suppose a random sample of 150 membership member shoppers who recently made a purchase on the web site yielded a mean amount spent of $60 and a standard deviation of $54. Complete parts (a) and (b) below. Question content area bottom Part 1 a. Is there evidence that the population mean amount spent per year on the web site by membership member shoppers is different from $49? (Use a 0.05 level of significance.) State the null and alternative hypotheses. Upper H 0: mu equals 49 Upper H 1: mu not equals 49 (Type integers or decimals. Do not round. Do not include the $ symbol in your answer.) Part 2 Identify the critical value(s). The critical value(s) is/are 1.96 comma negative 1.96