The writer of an email might include an emoticon:

a. because it is more formal.
b. to confuse the recipient.
c. to convey a certain tone.
d. because typing takes effort.

Martha participates in a research study in order to receive extra credit for her psychology class. when she arrives in the research office she is given a can of what looks and tastes like beer, but which actually contains no alcohol. in the adjoining room martha's classmate karen is also participating in the study. karen receives a can of alcoholic beer. if the experiment was designed to test the effects of alcohol on concentration, then who is exposed to the independent variable?