Four factors for improvements in transportation included:

1) Fulton's Folly: It was a steamboat by Robert Fulton. He did not invent it as some credited him for, but he was the first to make a commercial success out of it. The boat carried paying passengers from New York up to Albany.

2) Tom Thumb: The Tom Thumb was a steam locomotive that was used to showcase the American potential to create engine to Baltimore and Ohio Railroad.

3) The airplane: The airplane was a success, it was first used in WWI for combat, later people started to use it to transport mail. In WWII it was used as a mode of transportation. Later it was transformed as a common way of transport for all the people.

4) The Model T: The Model T was a car that was produced by Ford Motors. It was very common because it's price and because of this middle-class Americans were able to buy it and use it was a way of transport.

Four factors for improvements in transportation included Fulton's Folly.

Explanation:

Robert Fulton and Livingston built a steam boat called Clermont claimed monopoly to navigate on the river of Mississippi. The rivals charged that they did not invent a steamboat and hence they were granted only limited time to navigate. After 1824, monopolies were shattered.

Tom Thumb is the first Engine built in 1830. It replaced the stallion carriage.

Model T is the automobile built by Ford in 1903, its well-known for its stress-free maintenance and durability. Airplane is invented by Wright brothers which was a successful plane flight. These four factors constituted the improvements of Transportation.