7. Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate.

Student’s grades, A, B, or C, on a test.
Answer
A.Ratio
B.Interval
C.Ordinal
D.Nominal

8.Determine whether the given description corresponds to an observational study or an experiment.

A sample of fish is taken from a lake to measure the effect of pollution from a nearby factory on the fish.
Answer
A.Experiment
B.Observational study

9.Determine whether the given description corresponds to an observational study or an experiment.

A stock analyst selects a stock from a group of twenty for investment by choosing the stock with the greatest earnings per share reported for the last quarter.
Answer
A.Experiment
B.Observational study