Explanation:
A river formed by the confluence of the Allegheny and Monongahela Rivers in western Pennsylvania and flowing about 1,580 km (980 mi) to the Mississippi River at Cairo in southern Illinois. The British and French contested control of the river until 1763.
Answer:
In 1820, amid growing sectional tensions over the issue of slavery, the U.S. Congress passed a law that admitted Missouri to the Union as a slave state and Maine as a free state, while banning slavery from the remaining Louisiana Purchase lands located north of the 36º 30' parallel
Number 2 is true. Mexico hired empresarios to bring more people tp Texas because it wanted to colonize Mexico.
Number 4 is false. They had to convert to Catholicism, agree to Mexican law and not own sales.
Cross-checking information is important since it is one of the main methodological sources of validating knowledge in areas such as History, Law and Social sciences. Cross-checking is to History just as the scientific method to Physics. The claims and authenticity for example of some documents are validated through the use of this procedure.
The results of cross-checking information also occur in some settings where field research is carried. It can be used when engaging in anthropological or sociological research. An example of it is seen when interviews are carried in mental health institutions, to patients, to doctors, families, and surveys also are checked against people that are related to the object of study. These are corroborated with people who can help or provide unbiased knowledge on the inquiries. See below ... :)