What price do farmers get for their watermelon crops? In the third week of July a random sample of 41 farming regions gave a sample mean of x - $6.88 per 100 pounds of watermelon. Assume that o is known to be $1.96 per 100 pounds. (a) Find a 90% confidence interval for the population mean price (per 100 pounds) that farmers in this region get for their watermelon crop (in dollars). What is the margin of error (in dollars)? ( For each answer, enter a number, Round your answers to two decimal places.) lower limit upper limit margin of error (b) Find the sample size necessary for a 90% confidence level with maximal error of estimate = = 0.33 for the mean price per 100 pounds of watermelon. (Enter a number. Round up to the nearest whole number.) farming regions (c) A farm brings 15 tons of watermelon to market. Find a 90% confidence interval for the population mean cash value of this crop ( in dollars). What is the margin of error ( in dollars)? Hint: 1 ton is 2000 pounds. (For each answer, enter a number. Round your answers to two decimal places.) lower limit upper limit margin of error