solve this question plz

Think about a "bread & biscuit" factory haveing skilled, semi-skilled and unskilled man power. The rate of variation in the annual profit of the skilled man power is to be compared with the rate of variation in the annual profit of semi-skilled and unskilled man power. Considering a sample, the mean profit for skilled, semi-skilled and unskilled man power are taka 500000, taka 420000, taka 330000 with the standard deviation of taka 19500, taka 22000 and taka 22500 respectively. Now make a meaning full comparison with semi-skilled and unskilled manpower for skilled manpower by explaining your findings