Please leave equations with explanations. Am using to learn the concept.

At the beginning of the year, Craig Company had the following standard cost sheet for one of its plastic products: Details The actual results for the year are as follows: a. Units produced: 400,000 . b. Materials purchased: 2,060,000 pounds @ $3.95. c. Materials used: 2,100,000 pounds. d. Direct labor: 825,000 hours @ $14.85. Required: 1. Compute price and usage variances for materials. 2. Compute the labor rate and labor efficiency variances, using both the formula and columnar approaches