Density Curves and Normal Distributions Check Your Understanding: According to an article at africageographic.com there are many unexpected uses for elephant waste. But how much waste do elephants produce per day? Studies show that the distribution of amount of waste produced by adult elephants can be modeled by a Normal distribution with mean 250 pounds and standard deviation 21 pounds. a. What percent of adult elephants produce at least 300 pounds of waste in a day? b. A zoo has an agreement with the local farmers. They sell the daily waste from their elephant to the farmers for $5.00 per pound. If the amount of waste produced by the elephant on a given day is at the 10th percentile of the distribution of waste, how much