The following stemplot shows the swimming speeds, in kilometers per hour (km/h), for a random sample of 31 emperor penguins. Speed (km/h) 78 834 8 679 900134 9 5 5 6 7 8 8 9 10 0 11 23 10 5 8 8 8 11 0 23 115 Key: 718 = 7.8
(a) The mean of the sample is 9.771 km/h, and the standard deviation is 0.944 km/h. Construct and interpret a 95 percent confidence interval for the mean swimming speed of all emperor penguins in the population.
(b) Can the estimate of the mean swimming speed be generalized to all types of penguins? Explain your reasoning.