C. huge tunnels were built for sewer lines
In 1851 by Sir George Airy
<h2>

</h2>
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: consisted of organized labor, white southerners, african americans
Explanation:
these groups are all apart of roosevelt democratic coalition