A researcher is studying the effects of negative outcomes on the human brain in a psychological experiment. The researcher shows ten participants various pictures and designs. When the participants see a red star, they are immediately given a brief, painful shock and their brainwaves are analyzed. A different group of ten participants is given the same pictures and designs but are given no shock when they see the red star.
What was the control in the experiment?

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.

i don't see how you want other people to do your work for you and it is like you are just handing your assignment to anybody else and having them deal with it instead of your self i thought this site was for asking questions and somebody could you on it not just handing your work to somebody else to deal with it just saying don't mean to be mean just proving a fact.

explanation:

what the question i might be able to

in 1989, tiananmen square in beijing was the site of china’s main industries. china’s government headquarters. -pro-democracy demonstrations. (second choice)