The specifications for a manifold gasket that installs between two engine parts calls for a thickness of $\backslash (6\mathrm{.}0\backslash$mathrm$\{$~mm$\}\backslash$pm $\mathrm{.}2\backslash$mathrm$\{$~mm$\}\backslash ).$ The standard deviation of the process is estimated to be $0\mathrm{.}05$ mm $.$ What are the upper and lower specification limits for the gasket? The process is known to operate at a mean thickness of $6\mathrm{.}1$ mm $.$

A$.$ What is the process capability ratio?

B$.$ What is the process capability index?

Step by step would be great! Please do both A and B$!$ thanks in advance for all your help!