·1832 cyrus mccormick develops the mechanical reaper · 1837 john deere patents the steel plow · 1892 john froelich builds the first gasoline-powered tractor · 1895 refrigertion techniques developed in the u. s. which sector of the american economy would have been impacted most by the developments listed in this timeline? a) the energy sector b) the industrial sector c) the agricultural sector d) the communications sector

the correct answers are:

a - pacific plate;

it is the biggest oceanic tectonic plate. surrounded on all sides by continental tectonic plates, it is submerging and gradually becoming smaller and smaller.

b - north american plate;

huge continental plate, occupying big portion of the northern hemisphere.

c -eurasian plate;

alongside the north american plate, it is one of the two dominant continental plates in the northern hemisphere.

d - indian plate;

a small continental plate, that has been part of gondwanaland initially, but after the break up of it, moved towards northeast and pushed into the eurasian plate that was once part of laurasia.

they were destroyed coming out of the civil war but after he war they were booming. if you need an in-depth answer follow up with me  

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