The results of a national survey showed that on average, adults sleep 6.7 hours per night. Suppose that the standard deviation is 1.8 hours.

(a)Use Chebyshev's theorem to calculate the minimum percentage of individuals who sleep between 3.1 and 10.3 hours.

(b)Use Chebyshev's theorem to calculate the minimum percentage of individuals who sleep between 2.2 and 11.2 hours.

(c)Assume that the number of hours of sleep follows a bell-shaped distribution. Use the empirical rule to calculate the percentage of individuals who sleep between 3.1 and 10.3 hours per day. %How does this result compare to the value that you obtained using Chebyshev's theorem in part (a)?

The percentage obtained using the empirical rule is ---Select--- greater than lower than equal to the percentage obtained using Chebyshev's theorem.