6 ABC Corporation purchased and used 25,000 kg of materials for $1525 a ko. During the month they incurred 5,500 tabour hours for a total 5193,600 in direct labour costs. Standard costs are $16.50 ag for Materials and $35 75 tor labour Standards indicate that for the number of units completed they should have used 23,000 kg of materials and 6,400 hours of labour 7 A a) Determine the materials price and efficiency variances (4 marks) - b) What could have caused the variances in a? (1 mark) c) Determine the direct labour price and efficiency variances (4 marks) d) What could have caused the variances in C? (1 mark)