8 A transport company supplies the following details in respect of a truck of 5 ton capacity : Cost of truck Rs. 90,000 Estimated life 10 years Diesel, oil, grease Rs. 15 per trip each way Repairs and maintenance Rs. 500 per month Driver's wages Rs. 500 per month Cleaner's wages Rs. 250 per month Insurance Rs. 4,800 per year Taxes Rs. 2,400 per year General supervision charges Rs. 4,800 per year The truck carries goods to-and-from the city covering a distance of 50 km. each way. On upward trip freight is available to the extent for full capacity and on return only to the extent of 20% of capacity. Assuming that the truck runs, on an average, 25 days a month, work out : (a) Operating cost per ton-kilometre. (b) Rate per ton per trip that the company should charge, if a profit of 50% on freightage is to be earned