Answer:
Number 1
Explanation:
Although the ear began with Mazi German's attack on Poland in September 1939. The United States did not enyer the war until after the Japanese bombed the American fleet in Pearl Habour Hawaii on December 7, 1941
I know number 2 the bumps became very large
Answer:
The answer is double blind experiment.
Explanation:
In a double blind experiment, neither the researchers nor the participants are aware about which group is receiving the experimental treatment. This is done in order to prevent biases in the participants' judgment (the placebo effect), and prevent the researchers from giving accidental cues.
The greatest advantage of double blind studies is they have greater reliability and validity than other types of studies.
