Given: BM$=250$ m$,$ RR @ BM$=1\mathrm{.}000$ m$,$ squaredimensions$=8$mX$8$m$.$ According to the rod readings taken at each grid point, a$)$ draw a contour map with a $0\mathrm{.}5-$m contour interval b$)$ find the elevations of points B$3,$ C$4,$ and E$2.($Note: use a suitable drawing scale$).$