You attended a reunion of your high school class and noticed that several of your former classmates were doing quite well financially. You wondered if they were doing better than the national average salary for recent graduates published in 2015. You were able to conduct an anonymous random survey at the reunion, which revealed the following summary of annual salaries:

x = 56,975

s= 5,210

s^2 = 27,144,100

25 people completed the survey

a. statistically test whether their average salary is different from the national average of $53,500 in 2015. You may assume that salary follows a normal distribution. perform all 5 steps of hypothesis testing at