Isnt this a learning website and they are telling us the answers?

Sariah enters a room with several chirping crickets in it. upon first entering the room, sariah can hear the chirping; however, as she begins to talk to her friends, she is no longer aware of the chirping even though it is still there. the fact that sariah no longer perceives the chirping sound demonstrates sensory

Francisco loves to learn, but his lack of english makes him feel “nervous and scared.” why is he both happy and scared of school

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?