Depreciation factor $=0\mathrm{.}8$ and utilization factor $=0\mathrm{.}5.6-$ A drawing hall $40$ m $\backslash$times $25$ m is to be illuminatedwith lamps to an average illumination of $90$ lm$/$m$2$ with a mounting height of $5$ m$.$ Estimate suitablenumber and size of lamps. Sketch the spacing layout. Assume coefficient of utilization of $0\mathrm{.}5,$depreciation factor of $0\mathrm{.}8.$ Consider that $1$ S$/$H $1\mathrm{.}5$Size of lamps $200$W $300$W $500$WLuminous efficiency $($in lm$/$W$)161825$