$4.$ Accelerated tests run on an auto engine with the following number of hours running at high RPM

to failure:

Hours Median Rank $\%$

$2\mathrm{.}612\mathrm{.}9$

$7\mathrm{.}431\mathrm{.}4$

$13\mathrm{.}050\mathrm{.}0$

$21\mathrm{.}468\mathrm{.}6$

$42\mathrm{.}087\mathrm{.}1$

A$.$ What is the $\mathrm{.}95$ conformance level? $(2$ points$)$

B$.$ What does this mean? $(2$ points$)$

C$.$ What is the $0\mathrm{.}99$ conformance level? $(1$ point$)$

D$.$ At what number of hours would $95\%$ of the engines be expected to fail? $(1$ point$)$