The economy of the North was based mainly on Manufacturing. Many immigrants from Europe began working in factories and producing goods (cloth) in the North and Northeners believed that slavery should farther then where it already was
While The economy of the South was based on agriculture and they firmly believe that Slavery should spread due to the big profit of cotton that was picked by slaves
Sugar plantations, enslaved africans, ruthless plantation owners, strenuous manual labor
I am not completely sure but would it be answer number 4? Sorry if I am wrong, it just makes more since to me.
The option that does not explain why a large part of the Great Plains became known as the "Dust Bowl" would be that "<span>The soil of the Great Plains was too rocky to support farming," since the soil was (usually) relatively fertile. </span>
