Serve Robotics' stock plunged after Nvidia sold its stake in the company at the end of 2024, but the company has an enormous long-term opportunity.Nvidia (NVDA 0.41%) was valued at $360 billion at the start of 2023, but it has added almost$4 trillion to its market capitalization since then, thanks to surging demand for its artificial intelligence (AI) chips. The company is now spreading some of its wealth by investing in other AI enterprises. For instance, just last week, CEO Jensen Huang announced plans t ...