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Confidence intervals for population means

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An auto maker is interested in information about how long transmissions last. A sample of transmissions are run constantly and the number of miles before the transmission fails is recorded. The auto maker claims that the transmissions can run constantly for over $150,000$ miles before failure. The results of the sample are given below.

$\backslash$table$[[$Miles $(1000$s of miles$),],[$Mean$,150\mathrm{.}7],[$Variance$,4\mathrm{.}551],[$Observations$,42],[$Hypothesized Mean,$150],[$df$,41],[$Stat$,2\mathrm{.}17],[P(Tt)$ one$-$tail,$0\mathrm{.}018],[$Critical one$-$tail,$1\mathrm{.}683],[P(Tt)$ two$-$tail,$0\mathrm{.}036],[$Critical two$-$tail,$2\mathrm{.}02],[$Confidence Level$(95\mathrm{.}0\%),0\mathrm{.}665]]$

What is the level of significance?

What is the null hypothesis $H_0?$

What is the alternative hypothesis $H_a?$

Should $H_0$ be rejected or does $H_0$ fail to be rejected?

What conclusion can be drawn from the data?

Pick

What is the $95\%$ confidence interval for the mean life of a transmission?

$[$Ex$.1\mathrm{.}234$

Does the confidence interval support the results of the hypothesis test?

Pick $vv$

Why?