Guzzlers? environmental protection agency (epa) fuel economy estimates for automobile models tested recently predicted a mean of 24.8 mpg and a standard deviation of 6.2 mpg for highway driving. assume that a normal model can be applied. a) draw the model for auto fuel economy. clearly label it, showing what the 68–95–99.7 rule predicts. b) in what interval would you expect the central 68% of autos to be found? c) about what percent of autos should get more than 31 mpg?

Turrubiates corporation makes a product that uses a material with the following standards standard quantity 8.0 liters per unit standard price $2.50 per liter standard cost $20.00 per unit the company budgeted for production of 3,800 units in april, but actual production was 3,900 units. the company used 32,000 liters of direct material to produce this output. the company purchased 20,100 liters of the direct material at $2.6 per liter. the direct materials purchases variance is computed when the materials are purchased. the materials quantity variance for april is: