The consumption of diesel per hour of a bus varies directly as a square of its speed.When the bus is travelling at 40 kmph its consumption is 1 litre per hour.if each litre cost $40 and other expenses per hour is $40,then what would be the minimum expenditure require to cover adistance of 400 km?
(a)$600
(b)$700
(c)$800
(d)$900
(a)$600
(b)$700
(c)$800
(d)$900
