With reference to Exercise 8.5, test the null hypothesis that \(\sigma=0.75\) hours for the time that is required for repairs of the second type of bulldozer against the alternative hypothesis that \(\sigma>0.75\) hours. Use the 0.10 level of significance and assume normality.

Data From Exercise 8.5

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8.5 An investigation of two types of bulldozers showed that 50 failures of one type of bulldozer took on an average 6.8 hours to repair with a standard deviation of 0.85 hours, while 50 failures of the other type of bulldozer took on an average 7.3 hours to repair with a standard deviation of 1.2 hours. - (a) Test the null hypothesis 1 = 0 (namely, the hypothesis that on an average, it takes an equal amount of time to repair either kind of bulldozer) against the alternative hypothesis p - 20 at the level of significance, = 0.10.