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7-9 rely on the following data. Questions FrontGrade Systems allocates manufacturing overhead based on machine hours. Each connector should require 11 machine hours. According to the static budget, FrontGrade expected to incur the following 1,100 machine hours per month (100 connectors 11 machine hours per connector) $5,500 in variable manufacturing overhead costs $8,250 in fixed manufacturing overhead costs During August, FrontGrade actually used 1,000 machine hours to make 110 connectors and spent $5,600 in variable manufacturing costs and $8,300 in fixed manufacturing overhead costs. 7. FrontGrade's standard variable manufacturing overhead allocation rate is a. $5.00 per machine hour b$5.50 per machine hour. c. $7.50 per machine hour. d. $12.50 per machine hour. 8. Calculate the variable overhead cost variance for FrontGrade. a. $450 F b. $600 U c. $1,050 F d. $1,650 F 9. Calculate the variable overhead efficiency variance for FrontGrade a. $450 F b. $600 U c. $1,050 F d. $1,650EF