The answer to this question is B
1.1
2.3
3.2
4.4
5.4
6.2
7.1
8.3
9.2
Answer: it would be c and d
Explanation: hope this helps
Answer:
12 Technological Advancements of World War I
Tanks. In 1914, the “war of movement” expected by most European generals settled down into an unexpected, and seemingly unwinnable, war of trenches. ...
Flamethrowers. ...
Poison Gas. ...
Tracer Bullets. ...
Interrupter Gear. ...
Air traffic control. ...
Depth Charges. ...
Hydrophones.
Explanation: