asked to rate their cable companies on a five-point scale, with 1 being least satisfied and 5 most satisfied. The survey results are summarized in the following table: n1 = 174 n2 = 355 T = 3.51 2 = 3.24 $1 = 0.51 $2 = 0.52 a) Construct a point estimate and a 99% confidence interval for /1 - /2, the difference in average satisfaction levels of customers of the two companies as measured on this five-point scale. b) Refer to part a) concerning the mean satisfaction levels of customers of two competing cable television companies. Test at the 1% level of significance whether the data provide sufficient evidence to conclude that Company 1 has a higher mean satisfaction rating than does Company 2. Use the critical value approach. c) Use the p-value approach