(b) The first snow of the season begins to fall during the night. The depth of the snow, h, increases at a constant rate through the night and the following day. At 6 am a snow plough begins to clear the road of snow. The speed, vkm/h, of the snow plough is inversely proportional to the depth of snow. (This means v=hA where A is a constant.) Let xkm be the distance the snow plough has cleared and let t be the time in hours from the beginning of the snowfall. Let t=T correspond to 6 am. (i) Explain carefully why, for t≥T, 60, where 61 is a constant. (ii) In the period from 6 am to 63 am the snow plough clears 64 of road, but it takes a further 65 hours to clear the next kilometre. At what time did it begin snowing? Get tutor help
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