Compute the $R-$ factor for $1\mathrm{.}00in.$ thicknesses of glass. For the thermal conductivity of glass use $5\mathrm{.}00$Btu$*in\frac{.}{h}*f{t}^2*F.$

Express your answer in square foot degree Fahrenheit hours per British thermal unit.

$\{$:$R_{\text{g}\text{l}\text{a}\text{s}\text{s}}=,]f{t}^2*F*\frac{h}{B}tu$