Why was it necessary for countries involved in the war to take this approach?

Remember soh-cah-toasoh: cah: toa: now, looking at the picture we can see that we have an angle, the hypotenuse and want to find the value of the adjacent side to the angle. so we use cah to find the adjacent angle. plug in what we have: we need to solve for x now so we get it by itself on one side: plug this into your calculator and you'll find that:

It is c because it shows how the author is stating their own oppinion about the protagonist