Capital gain

I have a question regarding calculation of Capital gain. A partnership firm had sold its residential property and i have to compute the capital gain upon the same.... firm had purchased plot of land in 2002-03 and had constructed building upon the same plot  in 2006and  the firm had  sold the building in December 2012. Also, the firm had shown plot under the head fixed assets in the balance sheet.

My query is  whether i should apply section 32onbuilding( Depreciation on block assets) and   compute the indexation value of plot

Or

I shall apply section 32 on plot and building both....please help.....