Historically, the average time it takes KIm to swim the 200 meter butterfly is 148.4 seconds. Kim would like to know if her average time has changed. She records her time on 50 randomly selected occasions and computes the mean to be 147.8 with a standard deviation of 2.3 seconds. Determine the null and alternative hypothesis, and your conclusion at the level of significance .01. O HO: mu = 148.4 v.S. Ha: mu - 2.325, we cannot reject HO. O HO: mu = 148.4 v.s. Ha: mu is not equal to 148.4 T = (bar[X} - mu) / (S/sqrtin]) Since the observed value of the test statistics T_(obs] = -1.845 and [T_fobs]| 148.4 T = (bar[X] - mu) / (S/sqrtin]) Since the observed value of the test statistics T_(obs] = -1.845 and T_jobs] 1.96 we conclude that the average bridge repair cost is less than $25,003. O T_fobs} = 28.03, since T_fobs] > 1.645 we conclude that the average bridge repair cost is greater than $25,003. O T_fobs} = 3.78, since T_fobs] > 1.645 we conclude that the average bridge repair cost is greater than $25,003. O T_fobs} = 28.03, since T_fobs] > 1.645 we conclude that the average bridge repair cost is less than $25,003. O T_fobs] = 3.78, since T_fobs] > 1.645 we conclude that the average bridge repair cost is less than $25,003. O T_jobs] = 3.78, since T_fobs] > 1.96 we conclude that the average bridge repair cost is greater than $25,003. O T_fobs} = 28.03, since T_fobs] > 1.96 we conclude that the average bridge repair cost is greater than $25,003. O T_fobs} = 3.78, since T_fobs} > 1.96 we conclude that the average bridge repair cost is less than $25,003