E23-19 Calculating materials and labor variances Matthews Fender, which uses a standard cost system, manufactured 20,000 boat fenders during 2018, using 143,000 square feet of extruded vinyl purchased at $1.30 per square foot. Production required 400 direct labor hours that cost $16.00 per hour. The direct materials standard was seven square feet of vinyl per fender, at a standard cost of $1.35 per square foot. The labor standard was 0.028 direct labor hour per fender, at a standard cost of $15.00 per hour. Compute the cost and efficiency variances for direct materials and direct l the pattern of variances suggest Matthews Fender's managers have been making trade- offs? Explain. abor. Does