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Sara's Systems manufactures audio systems for cars. Two models are produced: The Standard model has a budgeted price of $185 and a standard variable cost of $65. The Blaster model has a budgeted price of $465 and a standard variable cost of $145. At the beginning of the year, Sara estimated that she would sell 5,940 Blaster models and 23,760 Standard models. The actual results for the year showed that 7,470 Blaster models were sold for total revenues of $3,062,700. A total of 25,400 Standard models were sold for revenues of $5,842,000. Required: a. Compute the activity variance for the year. b. Compute the mix and quantity variances for the year. Complete this question by entering your answer below. Compute the activity variance for the year. (Do not rol calculations. Indicate the effect of each variance by se favorable, or "U" for unfavorable. If there is no effect, option.)