Juan wants to compare the effectiveness of two drugs in treating migraines. he administers drug a to a participant and then drug b to the same participant eight hours later when drug a is still in the participant's system. in this case, the study is contaminated by a effect.

Hi there! an adjective is a word that describes the state or quantity of a noun. it modifies the meaning of the noun itself. in the passage, the following words are adjectives: (1) drifting, (2) narrow, (3) thick, (4) chill, (5) completely, (6) quiet, (7) little and (8) pitoresque.reminder: "softly" isn't an adjective but an adverb, because it describes the state of a verb instead of a noun.