According to the IRS, individuals filing federal income tax returns prior to March 31 received an average refund of $1,062 in 2018. Consider the population of "lastminute" filers who mail their tax return during the last five days of the income tax period (typically April 10 to April 15). a. A researcher suggests that a reason individuals wait until the last ve days is that on average these individuals receive lower refunds than do early lers. Develop appropriate hypotheses such that rejection of Ho will support the researcher's contention. Ho: M is Ha: [L is - Select your answer- V b. For a sample of 400 individuals who led a tax return between April 10 and 15, the sample mean refund was $910. Based on prior experience a population standard deviation of a = $1,800 may be assumed. What is the p-value (to 4 decimals)? c. Using a = 0.05, can you conclude that the population mean refund for "last minute" lers is less than the population mean refund for early lers? - Select your answer - V d. Repeat the preceding hypothesis test using the critical value approach. Using a = 0.05, what is the critical value for the test statistic (to 3 decimals)? Enter negative value as negative number. State the rejection rule: Reject Ho if z is the critical value. Using the critical value approach, can you conclude that the population mean refund for "last minute" lers is less than the population mean refund for early lers? - Select your answer - v