How did railroad owners use crédit mobilier to make huge, undeserved profits?

By charging too much for railroad construction and paying off government officials

Explanation:

In the United States there was a festival of embezzlement during the construction of Rail Road Union Pacific. All this embezzlement became known as Credit Mobilier, which was a embezzlement scheme where the shareholders responsible for building the Pacific railroad overcharged for the construction of the railroad (sometimes triple the correct price) and shared the profits between them.

A scandal involving Union Pacific, contracted to build the railroad, and its subsidiary Crédit Mobilier, broke out in 1872, thanks to a scoop from The Sun. It hit executives, eight senators, some 30 deputies, and even Vice President Schuyler. Colfax The career of some politicians was ruined, but one of the deputies, after getting rid of the accusations, became President James Garfield.

it would have to be gasioline