Question 1057595
Ho:lifetime is 220,000 miles.  I think 22,000 miles was a typographical error.
Ha: it isn't
alpha=0.01
test statistic is a t (0.995, df=22) 
critical value, |t|>2.819
equation (xbar-mean)/s/sqrt (23)
t=(220,000-226,450)/11500/sqrt (23)
=-6450*sqrt(23)/11500=-2.69
The null hypothesis is not rejected at the 0.01 level. The mean lifetime may be 220,000 miles