Was Crocodile stronger at Marineford? Or was he holding back in Alabasta?

 During the Alabasta arc, Crocodile displayed a level of power that was initially considered overwhelming by the Straw Hat Pirates. He possessed the Logia-type Devil Fruit called the Suna Suna no Mi (Sand-Sand Fruit), which granted him the ability to control and transform into sand. He had a reputation as a Shichibukai and controlled the desert kingdom of Alabasta from the shadows. His strength was showcased through his battles with Luffy and others. At Marineford, Crocodile was present as part of the war that took place at Marine Headquarters. While he did participate in the battle, he didn't display the same level of dominance as some other powerful characters present. This has led fans to speculate that he might not have been as strong as initially portrayed in Alabasta. It's important to note that power scaling and character abilities can be subject to interpretation and development by the author. Oda often keeps details deliberately open-ended to keep the story intriguing.

How far apart are train tracks in the United States of America?

 The distance between train tracks, also known as the track gauge, can vary in the United States. The most common track gauge in the U.S. is 4 feet 8.5 inches, which is known as standard gauge. This gauge is used by most freight and passenger railroads in the country.

There are also narrow gauge railroads in the U.S., which have track gauges that are smaller than standard gauge. These railroads are typically used in mountainous or rural areas where it is not practical to use standard gauge tracks. The track gauges of narrow gauge railroads in the U.S. can vary, but they are typically between 2 feet 6 inches and 3 feet.

In addition, there are also some railroads in the U.S. that use broad gauge, which is a track gauge that is wider than standard gauge. These railroads are less common in the U.S. and are primarily found in the eastern part of the country. The track gauge of broad gauge railroads in the U.S. is typically around 5 feet 6 inches.

It is important to note that the track gauge can vary from one railroad to another, even within the same country.