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Zodiac Fabrics Ltd is a manufacturer of men's clothing. The company uses a standard costing system. During May 2022, the firm produced 4,800 shirts. The actual and standard costs per shirt for May 2022 were as follows: Quantity per shirt Cost per metre / hour (in ) Standard: Direct Materials Direct Labour Variable Overhead Fixed Overhead Actual: Direct Materials Direct Labour Variable Overhead Fixed Overhead 4 metres 1.6 hours 1.6 hours Per unit 3.60 4.50 1.8 9 4.4 metres 1.4 hours 1.4 hours Per unit 13.35 4.85 2.15 9.10 There was no inventory of materials in hand at the beginning of May. During the month, a total of 21,120 metres of material were purchased all of which were used during the month. Zodiac reported the following information during May: Shirts Standard 5,000 Actual 4,800 Required: a) Calculate the following: i) Material price variance ii) Material usage variance iii) Labour rate variance iv) Labour efficiency variance v) Fixed overhead efficiency variance vi) Fixed overhead volume variance vii) Variable overhead efficiency variance viii) Total labour variance ) (20 marks) b) Explain the possible reasons for variances in the labour rate and labour efficiency