Can man communicate with a machine through brain-wave processing? This question was the topic of research reported in IEEE Engineering in Medicine and Biology Magazine (Mar. 1990). Volunteers were wired to both a computer and an electroencephalogram (EEG) monitor. Each subject performed five tasks under two conditions—eyes opened and eyes closed.

a. Determine the number of experimental conditions under which each subject was tested.
b. List the conditions of part a.
c. Two measurements were recorded for each subject— one after 2 seconds of artifact-free EEG and one after only .25 second of artifact-free EEG. What is the total number of measurements obtained for each subject?