Which of these technologies was able to spread because of the growth of american railroad networks ?
a. the electric light bulb
b. the telegraph
c. the mechanical harvester
d. the internal combustion engine

d. the internal combustion engine

Explanation:

There's a type of railway locomotive in which diesel is the prime mover. This type of railway locomotive is called "A diesel locomotive."

Many different types of these were made, but the main different is usually on how the mechanical power is conveyed to the driving wheels.

Early Internal Combustion locomotives at first used kerosene and gasoline as fuel, but eventually, they were improved. In 1898, steel engines reduced sized and improved power of the locomotives.

du boi was considered a radical because he wanted the immediate end for segregation. the biggest different between him and booker t. washington is that, even though washington believed that segregation should be considered illegal, he did not believe at all that a law was needed to keep blacks away from whites and that this would be something natural (to have the races apart) for a long time until society adjusted, while du boi believe that agitation was the only way to end segregation.

d is the right answer