I believe the answer is: The presence or absence of music
independent variable refers to the type of variables that are not influenced by other variables. This represent the things that can be controlled by the researchers in order to ignite a certain causal relationship with the dependent variables ( the things they want to measure)
There was a number of reasons. The articles of confederation didn't enable the central government to collect taxes. There was no National court to solve international conflicts. And many states took advantage of a missing strong leading figure in the form of a president. The Articles of Confederation was week due to giving too much power to the central government.
I think that due to the number of casualties on both sides neither side was a clear winner
An inherent problem in using secondary sources of data is that the data might have been manipulated a bit
Because both wanted power over North America and also they wanted land.