What volume of snow will be shoveled, plowed or otherwise removed from paved surfaces in the United States this winter?

We know that the center of the Milky Way contains a supermassive black hole because we have observed a star orbiting it with a very small minimum distance (“perihole”?). What is the maximum speed of that star?

Supplementary Material

AAPT members receive access to The Physics Teacher and the American Journal of Physics as a member benefit. To learn more about this member benefit and becoming an AAPT member, visit the Joining AAPT page.