Which of the following did it apply tot he efforts made by the doughboys for the american force in the war?
a. they never led by general john j pershing
b. they over threw the russian government
c. they fought the last german offense in france d. they improved the allies’ morale to win the war

1775 is your answer hope this

germany

explanation:

a rocket engine utilizes collected rocket explosive mass for producing its high-speed propulsive jet. rocket engines are effect engines, achieving thrust in accordance with newton's third law. maximum rocket engines use flaming, although non-combusting methods (such as cold gas thrusters) also exist.