Labor is usually described as hard, physical work. The best answer would be C. work for which people get paid.
I'm pretty sure the first one is not a crater lol. The last one is a crater, the second one I think is a rift valley, and the first one volcano. Not sure tho as the image is not that clear but the last one is a crater.
Features of evidence for the Pacific Ocean's maturity include the ridges that are found in its zone. A ridge (where plates are formed) is an underground mountain range formed over a long period of time. Evidence of these and recycled trenches in the area point to the Pacific Ocean's maturity.
The area of square a is 100
