How can volcanic eruptions affect the earths atmosphere?

What is the "great pacific garbage patch"? (a) a large area of marine debris concentrated by rotating ocean currents (b) a large area around the pacific rim where debris collects from natural disasters such as tsunamis (c) an area in the pacific ocean where trash is intentionally dumped due to lack of landfill availability (d) a large trash dump located in hawaii

One reason that madrid became the capital of spain is because of its

The caste system in india was used for what purpose? a) to ensure that all people had an adequate income b) to prevent the rich from taking too much power c) to provide social control and conformity according to one’s birth d) to draft a military capable of defending india from mongol invasion