Read the original and improved research questions.
original: what is the relationship between natural resources and the industrial revolution?
improved: how did coal contribute to the industrial revolution in pittsburgh in the 1880s?
which of the basic question words improve this research question? select three options.
how
what
when
where
why

The primary question words that had assisted in enhancing the given research question would be:

A). How

B). What

C). When

Hence, options A, B, and C are the correct answers.

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What, how, when

Be specific and stick to a topic.  Know your source and understand how something came to pass or work.  It is always important when doing research to understand when something occurred so you can accurately complete your research.

Explanation:

i dont know but i need points

confederacy: supported slavery, believed states should be able to nullify federal laws, supported low tariffs

union: everything else