The director of cost management for Portland Instrument Corporation compares each month's actual results with a monthly plan. The standard direct-labor rates for the year just ended and the standard hours allowed, given the actual output in April, are shown in the following schedule Standard Direct-Labor Standard Direct Libor Pours Rate per Allowed, bien Ancil Output Labor class IIT 5.246.28 1,200 Labor class 11 21.20 1,200 Labor class 1 15.20 1,200 A new union contract negotiated in March resulted in actual wage rates that differed from the standard rates. The actual direct-labor hours worked and the actual direct-labor rates per hour experienced for the month of April were as follows Labor class 111 Labor class 11 Labor class 1 Actul Direct Labor Hate per Hour $26.00 22.70 16.40 Actual Direct Labor Hours 1,300 1,500 950 Required: 1-o. Compute the direct labor rate variance for each labor class for the month of April 1-b. Compute the direct-labor efficiency variance for each labor class for the month of April 2. Which of the following could be considered an advantage of using a standard-costing system in which the standard direct labor rates are not changed during the year to reflect such events as a new labor contract