Given: length (1) of box =1.5  m Breadth (b) of box =1.25  m Depth (h) of box = 0.65  m (i) Box is to be open at topArea of sheet required.=2 h+2bh+lb =[2×1.5×0.65+2×1.25×0.65+1.5×1.25]m2 =(1.95+1.625+1.875)m2=5.45 m2 (ii) Cost of sheet per m2 area = Rs. 20.Cost of sheet of 5.45 m2 area = Rs(5.45×20) = Rs. 109