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Q1- Two plants were installed by a certain textile mills on the same date and were in operations under similar conditions. Their first six month's output is given below; MONTHS Plant 1 Plant II [units] (units) January 10,000 20,000 February 30,000 25,000 March 10,000 25,000 April 30 000 25,000 May 45,000 30.000 June 25,000 10.000 Total 150.000 135,000 Required: Calculate the variance in output for these two plants