Final answer:
A potential eruption of Mount Rainier could be more destructive than the 1980 Mt. St. Helens eruption because it is closer to populated areas and its extensive glaciation could produce far-reaching lahars, affecting more people and property.
Step-by-step explanation:
An eruption of Mount Rainier similar to the 1980 eruption of Mt. St. Helens could be considerably more destructive due to several factors. Mount Rainier is located closer to densely populated areas, including the Seattle metropolitan area, increasing the potential for human casualties and property damage. Furthermore, Mount Rainier is heavily glaciated, and an eruption could cause catastrophic lahars—volcanic mudflows—far more extensive than those at Mt. St. Helens, potentially reaching populated areas. The 1980 eruption of Mt. St. Helens caused a massive landslide that wiped out vegetation, deposited volcanic ash, and resulted in the formation of new valleys through erosion. This eruption was a significant geological event that reshaped the local landscape and dramatically altered the regional ecosystem.