The time needed for checking in at a motel is to be investigated. Historically, the process has had a standard deviation equal to $0\mathrm{.}132.$ The means of $39$ samples of $n=14$ are

$\backslash$table$[[$Sample$,$Mean,Sample,Mean,Sample,Mean,Sample,Mean$],[1,3\mathrm{.}86,11,3\mathrm{.}88,21,3\mathrm{.}84,31,3\mathrm{.}88],[2,3\mathrm{.}90,12,3\mathrm{.}86,22,3\mathrm{.}82,32,3\mathrm{.}76],[3,3\mathrm{.}83,13,3\mathrm{.}88,23,3\mathrm{.}89,33,3\mathrm{.}83],[4,3\mathrm{.}81,14,3\mathrm{.}81,24,3\mathrm{.}86,34,3\mathrm{.}77],[5,3\mathrm{.}84,15,3\mathrm{.}83,25,3\mathrm{.}88,35,3\mathrm{.}86],[6,3\mathrm{.}83,16,3\mathrm{.}86,26,3\mathrm{.}90,36,3\mathrm{.}80],[7,3\mathrm{.}87,17,3\mathrm{.}82,27,3\mathrm{.}81,37,3\mathrm{.}84],[8,3\mathrm{.}88,18,3\mathrm{.}86,28,3\mathrm{.}86,38,3\mathrm{.}79],[9,3\mathrm{.}84,19,3\mathrm{.}84,29,3\mathrm{.}98,39,3\mathrm{.}85],[10,3\mathrm{.}80,20,3\mathrm{.}87,30,3\mathrm{.}96,,]]$

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a$-1.$ Construct an $\stackrel{}{x}-$chart for this process with three$-$sigma limits$.($Do not round intermediate calculations. Round your answers to $2$ decimal places.$)$