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.

When, where, and how was money used in the world?

 Money has been used in various forms throughout history and in different parts of the world. The use of money as a means of exchange for goods and services can be traced back to ancient civilizations, such as the Sumerians, who used a system of clay tablets with specific values to facilitate trade.

In ancient Greece, money in the form of coins made of precious metals, such as gold and silver, began to be used around 600 BC. The Romans also used coins made of precious metals, and the use of coins as a form of money spread throughout the Roman Empire and into other parts of Europe.

In modern times, paper money, backed by a government or other authority, has become the most common form of money in use around the world. However, electronic forms of money, such as credit cards, debit cards, and digital currencies, have also become increasingly prevalent in recent years.

The use of money has evolved over time and has played a central role in the development and functioning of human societies. It allows for the exchange of goods and services and facilitates the efficient allocation of resources.