Question

why would a mechanical reaper be an improvement for farmers? it would save them time and labor. it would allow them to plant other crops. it could be used for breaking up the soil of the prairie. who would benefit most from john deeres plow? farmers on the frontier plantation owners in the south grain farmers in pennsylvania

Explanation:

John Deere's plow was designed to break through the tough prairie soil. Frontier farmers faced this challenging soil type. While plantation owners in the South had different soil conditions (more focused on cash crops like cotton with different tilling needs) and grain farmers in Pennsylvania had different soil (not the thick prairie sod), frontier farmers specifically needed tools to work the prairie land. John Deere's plow, with its steel blade, was effective for this purpose.

Answer:

farmers on the frontier