9. The purpose of statistical inference is to provide information about the.

a. sample based upon information contained in the population.

b. population based upon information contained in the sample.

c. population based upon information contained in the population.

d. mean of the sample based upon the mean of the population.

10. Random samples of size 81 are taken from an infinite population whose mean and standard deviation are 200 and 18, respectively. The distribution of the population is unknown. The mean and the standard error of the mean are.

a. 200 and 18.

b. 81 and 18.

c. 9 and 2.

d. 200 and 2.