standard costing and variances

Question : The Perseus Co a medium sized company, produces a single product in its one overseas factory. For control purposes, a standard costing system was recently introduced. The standards set for the month of May were as follows: Production and sales 16,000 units Selling price (per unit) $140 Materials: Material 007 6 kilos per unit at $12.25 per kilo Material XL90 3 kilos per unit at $3.20 per kilo Labour 4.5 hours per unit at $8.40 per hour Overheads (all fixed) $86,400 per month. (They are not absorbed into the product costs) The actual data for the month of May is as follows: Produced 15,400 units which were sold at $138.25 each Materials: Used 98,560 kilos of material 007 at a total cost of $1,256,640 and used 42,350 kilos of material XL90 at a total cost of $132,979. Labour: Paid an actual rate of $8.65 per hour to the labour force. The total amount paid out, amounted to $612,766. Overheads (all fixed): $96,840 Required: compute for a. material price and usage variance for material x & y b. labour rate and hours variance c. sales price & sales volume variance