Plants have these because root nodules<span> are formed when nitrogen fixing bacteria called "rhizobia" start to enter the cells of a host </span>plant<span>. Rhizobia normally live inside of the soil and they </span>can<span> exist without a host </span>plant<span>.</span>
The Northeast became a leader in commerce because of its location and early development of industrial industries. The Northeast became a manufacturing hub in the colonies and in the newly formed United States which created specialization and the growth of commerce in this region relative to the South which was more agriculturally based.
Answer:
A and B.
Explanation:
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