Some felt industrialists like Vanderbilt were captains of industry because A. They created jobs and economic wealth,
B. They were good steamboat captains on the Mississippi.
C. They carried out fair labor practices,
D. They were excellent managers of natural resources,

a

Explanation:

they exploited new technologies, e.g., railroads, steel, electricity, to introduce new more efficient and effective processes and methods to transport materials, build new structures, e.g. bridges, taller buldings, and power factories and homes, etc , all of which created new jobs and improved the standard of living. .

the population grew a lot and was making more money

the perimeter of a triangle is 69 cm. side a is 5 cm shorter than side b. side c is twice as long as side a. find the length of each side. i need to know how to do it in 2 equations.  

equations:

a = b-5

c = 2a

a + b + c = 69