List the 3 major eras from past to present.

idk

explanation:

that would be called plucking : )

explanation:

''plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". as a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock."

the cost of mining is extremely low compared to the money earned from mining, creating income to improve the environment.