9.A)Calculate the 95% confidence interval for the mean using the given population standard deviation. Assume that the data come from a normally distributed population.

When individuals become infected with malaria the parasite consumes red blood cells, causing the patient to become anemic. Red blood cell concentration was measured in a group of18 mice,giving the following data, measured as(cells10⁶)/L.

3.2 4.53.73.32.53.6

3.8 3.64.23.52.03.1

2.6 2.96.94.57.33.0

Suppose the population standard deviation is(1.310⁶) cells/L. (Round your answers to one decimal place.)

_________ to _______ millions/L

B)Twenty individual seals from Antarctica were weighed, giving the following data (in pounds).

903 920 923 931 937

939 946 948 950 951

956 959 960 964 968

971 976 982 986 992

Calculate the sample standard deviation. (Round your answer to two decimal places.)

C)A study measured the number of external parasites on a sample of 20 damselflies, giving the following data.

50054 5

12 28 24365

55 4314 4212

61 3633 58 23

Calculate the sample standard deviation. (Round your answer to two decimal places.)