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SM Ltd manufactures a single product L, for which the standard material cost is as follows. Material 14kgx3/= Kshs per unit 42.During July ,800 units of L were manufactured, 12,000kgof material were purchased for kshs 33,600, of which 11,500kgwere issued to production.SM Ltd value all stock at standard cost. The material price and usage variances for July were: Select one: a. Kshs2,400 (F) (price) Kshs 900 (A) (Usage) O b. Kshs 2,300 (F) (price) kshs 900 (A)(Usage) O C. Kshs 2,300 (F) (price) kshs 300 (A) (Usage) O d. Kshs 2,400 (F) (price) Kshs 840 (A) (Usage)