Answer: c, <em>harsh weather condition.
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PS. </em><em>IM NOT CHEATING, IT JUST LOOKS LIKE IT. </em>
The united states signed the Louisiana purchase with France.
Dred Scott was an enslaved man whose Missouri slaveholder had taken him to live in free territory before returning to Missouri. Assisted by abolitionists, Scott sued to end his slavery, arguing that the time he had spent in free territory meant he was free.