Answer:
Military communications have to be coded to keep them secret from the enemy. However the process of coding and decoding are time consuming processes. Furthermore the codes may be broken by the enemy. Nations have devoted considerable effort trying to create unbreakable codes. In World War II both Germany and Japan thought they had such unbreakable codes, but in fact these codes were broken and their most vital information were readily available to their enemies.
Explanation:
Answer:
Railroads used the iron to build railroad tracks but iron was weak and also dangerous. Soon people then realized that steel was a better material for tracks because it was able to hold more weight which then allowed heavier cargo. Railroads also transported mineral needed to forge steel.
Explanation:
B. The Wright brothers . . .

<span>Because Athens was using money from the Delian League.</span>