When going more than 38 miles per hour, the gas mileage of a certain car fits the model 4072-01-02-03-00_files/i012.jpg where x is the speed of the car in miles per hour and y is the miles per gallon of gasoline. based on this model, at what speed will the car average 15 miles per gallon? (round to nearest whole number.) a. 149 c. 48 b. 98 d. 73

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?