The answer is B/2
hope this helps
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Earth's mass has remained constant, and thus the gravitational pull at the surface has decreased over time; Earth's mass has grown with the volume in such a way that the surface gravity has remained constant; Earth's gravity at its surface has increased over time, in line with its hypothesized growing mass and volume.
Answer:
technological advancements has led to higher relative demand for skilled workers and a lower elative demand for workers preforming routine activities