Cross-sectional study is a kind of research which compares different population groups at one specific point in time.
Here, the researcher compares three population groups (first grade, third grade, and sixth grade of elementary school). By using this method, any differences between age groups regarding reasoning ability can be related to age differences not something that happened over time.
<h2>The following is the order of events that led to the United States joining World War II based on their occurrence:
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<u>Fascist dictators rise to power and World War I begins: </u>The rise of the Japanese Emperor who bore imperialistic ideology culminated in the early tensions between different nations which eventually resulted in World War I.
<u>The Lend-Lease Act provides Military aid to Allied Forces while the U.S. remains neutral:</u> The United States chose to stay out of the war but help its allies in the war by providing war equipment.
<u>Japan feels threatened and attacks the U.S. naval base at Pearl Harbor, Hawaii:</u> Owing to the help extended by the United States to its allies, Japan chooses to teach the US a lesson by bombing one of the naval bases of the US Navy.
<u>The United States enters into World War II:</u> After the attack on the US Naval base done by Japan, the US decides to participate in the war in order to bring it to an end.
