On April 1, 2009 a furnace was purchased for ₹ 2,70,000. Estimated useful life of this furnace is 25,000 hours with an estimate of salvage value ₹ 20,000 at the end. During the year 2009–10, the furnace was put to use for 4,100 hours and during 2009–10 it was used for 4,250 hours of working. Show how depreciation and book value of the furnace is to be recognized in the annual accounts.