Answer:
Gas
Machine Guns
Trenches
Explanation:
ww1 was all about using mustard gas and it was popularized before being banned after ww1 and ww1 was the first introduction to full auto machine guns similar to LMGs nowdays and trenches were created to prevent getting shot, gassed or sprayed down by enemies
Andrew Johnson Wrote his own Reconstruction plan after becoming president
Answer:
4 but the debts from ww1 were not paid fully till 2013
Explanation:
The answer is B, skilled workers