$8\mathrm{.}21.$ The data in Table $8$E$.6$ were taken by one operator during a gauge capability study.

a$.$ Estimate gauge capability.

b$.$ Does the control chart analysis of these data indicate any potential problem in using the gauge?

Table $8$E$.6$ Measurement Data for Exercise $8\mathrm{.}21$

$\backslash$table$[[\backslash$table$[[$Part$],[$Number$]],$Measurements,$\backslash$table$[[$Part$],[$Number$]],$Measurements$],[1,2,1,2],[1,20,20,9,20,20],[2,19,20,10,23,22],[3,21,21,11,28,22],[4,24,20,12,19,25],[5,21,21,13,21,20],[6,25,26,14,20,21],[7,18,17,15,18,18],[8,16,15,,,]]$