What are the key differences between the M87 black hole and Sagittarius A, and how do these differences impact our understanding of black holes in the universe?

The key differences between the M87 black hole and Sagittarius A are their size and activity levels. M87 is much larger and more active, while Sagittarius A is smaller and less active. These differences impact our understanding of black holes by providing insight into the range of sizes and behaviors they can exhibit, helping us to better understand the diversity of black holes in the universe.