Three anticoagulant drugs are £€¢ studied to compare their effectiveness in dissolving blood clots. Each of five subjects receives the drugs at equally spaced time intervals and in random order. Time periods between drug applications permit a drug to be passed out of a subject's body before the subject receives the next drug. After each drug is in the bloodstream, the length of time (in seconds) required for a cut of specified size to stop bleeding is recorded. The results are shown in the following table.

a. What type of experimental design was used in this study? Identify the response, factor(s), factor type(s), treatments, and experimental units.
b. Is there evidence of a difference in mean clotting time among the three drugs? Test using a = .10.
c. What is the observed significance level of the test you conducted in part a? Interpret it.
d. Was blocking effective in reducing the variation among the data? That is, do the data support the contention that the mean clotting time varies from person to person?
e. If warranted, use a multiple comparisons technique to determine whether one of the drugs is most effective. Use an overall significance level of α = .10.

50138 58021 01 .7 34 B 29 21 44 74 22147 56357 | A 27 8 5 30, 3158 s-12345