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 $1.92 per 100 pounds. {a} Find a 90% condence 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 :3; upper limit $ margin of error $ (b) Find the sample size necessary for a 90% condence level with maximal error of esb'mate E = 0.39 for the mean price per 100 pounds of watermelon. {Enter a number. Round up to the nearest whole number.) E farming regions {c} A farm brings 15 tons of watermelon to market. Find a 90% condence 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 $