Shawarma Shack Ltd uses a standard marginal costing system. Details for one of its products,Shawarma Kit, are as follows:Standard per Batch of Shawarma Kit AEDSelling Price $60$Materials $4$ Kg @ $8$ per Kg $32$Labour $2$ hours @ $5$ per hour $10$Gross Profit $18$The budgeted output and sales for the period were $6,000$ batches of Shawarma Kit.Actual Results for the month just ended were as follows:Output: $6,500$ batches were produced and sold.Turnover: $312,000$Materials: the total cost of the $27,000$ Kgs purchased and used was $184,000.$Labour: the workers were paid a total of $71,000$ for working $13,750$ hours.

Part $($a$)$Calculate the following variances:Sales Price

Sales Volume

Overall Material Variance

Material price

Material usage

Overall Labour Variance

Labour rate

Labour efficiency.

Part $($b$)$Suggest possible reasons for the following variances that you have calculated:Sales Price

Material Usage

Labour Efficiency