1. Why do some geologists believe that Pangaea was the most recent in a succession of supercontinents? 2. Why are active volcanoes, such as Mount St. Helens, usually located in mountain ranges along...

1. Why do some geologists believe that Pangaea was the most recent in a succession of supercontinents?

2. Why are active volcanoes, such as Mount St. Helens, usually located in mountain ranges along the boundaries of tectonic plates?

3. Why is more lunar detail visible through a telescope when the Moon is near quarter phase than when it is at full phase?