The factor that helped the United States in making the inland transportation and commerce to be possible is in letter C. The intricate river system. I hope you are satisfied with my answer and feel free to ask for more if you have clarifications and questions.
The national network of waterways, ports, and intermodal landside links allowed the multiple modes of transportation that was water-based. The system included privately as well as publically owned commerce-carrying ships or vessels, navigable or passable waterways, more than about 350 ports, about 40,000 kilometers of navigable channels, shipyards, facilities for the repairing of vessels, recreational marinas and a fully trained labor staff that operated and maintained the whole foundation or an entire infrastructure we can say. Users of the waterway system each year included port calls for commercial vessels, fishing vessels, and recreational vessels. In this way, inland transportation and commerce became possible in the United States.
Coal is called a fossil fuel because it was made from plants that were once alive! Since coal comes from plants, and plants get their energy from the sun, the energy in coal also came from the sun.
The quartz is more resistant to abrasion and chemically more resistant than the feldspar. The result is that the quartz remains in the stream but the feldspar breaks down to clay or is dissolved.