Records on a fleet of trucks reveal that the average life of a set of spark plugs in normally distributed with a mean of 22,100miles. the fleet owner purchased 18 sets and found that the sample average life was 23,400 miles; the sample standard deviation was 1,412 miles. to determine if the spark plugs average 22,100 miles, what is the critical value for the test using a 0.05 level of significance?

Which curve shows increasing opportunity cost as you give up more of one option? demand curve bow-shaped curve yield curve indifference curve

Data for hermann corporation are shown below: per unit percent of sales selling price $ 125 100 % variable expenses 80 64 contribution margin $ 45 36 % fixed expenses are $85,000 per month and the company is selling 2,700 units per month. required: 1-a. how much will net operating income increase (decrease) per month if the monthly advertising budget increases by $9,000 and monthly sales increase by $20,000? 1-b. should the advertising budget be increased?

As a result of a labeling mistake at the chemical factory, a farmer accidentally sprays weedkiller rather than fertilizer on half her land. as a result, she loses half of her productive farmland. if the property of diminishing returns applies to all factors of production, she should expect to seea. a decrease in the marginal productivity of her remaining land and an increase in the marginal productivity of her labor. b. an increase in the marginal productivity of her remaining land and an increase in the marginal productivity of her labor. c. an increase in the marginal productivity of her remaining land and a decrease in the marginal productivity of her labor. d. a decrease in the marginal productivity of her remaining land and a decrease in the marginal productivity of her labor.