Assume that we want to construct a confidence interval. Do one of the following, as appropriate: (a) find the critical value to/2, (b) 40- find the critical value Za/2, or (c) state that neither the normal 30- distribution nor the t distribution applies. Frequency 20- The confidence level is 95%, o is not known, and the histogram 10- of 59 player salaries (in thousands of dollars) of football players on a team is as shown. 0 4000 8000 12000 160 Salary (thousands of dollar O A to a /2 (Round to two decimal places as needed.) O B. Zx/2 =