$6-48.$ It has been decided that whole body scanning technology will be used for airport security purposes. Two types of devices are being considered at a certain airport $($only one will be selected$)$: back scatter $(B)$ and millimeter wave $(W).$ The selected scanning equipment is to be used for six years. The economic decision criterion at this airport is to meet or exceed a $15\%$ annual return on its investment. Based ar the data found in Table P$6-48,$ which scanner should be selected? Use the PW method of analysis. Which rule, Section $6\mathrm{.}2\mathrm{.}2,$ did you use in your analysis? $(6\mathrm{.}5)$

Table P$6-48$ Table for Problem $6-48!$

$\backslash$table$[[$Factor$,B,W$