All along 19th St NW, between DuPont Circle to the North and Pennsylvania Ave NW to the South, are a whole bunch of art pieces on display. All are easily accessible/viewable from the sidewalk, a few are in building lobbies, but you do NOT have to enter any building to find the answers and the art pieces are all available 24/7. Find them and answer questions about the art pieces or the locations to uncover the coordinates of the physical cache. Which is a magnetic nano.
The physical container is located at N 38° 54.ABC′ W 77° 02.DEF′. Photos of most of each art piece are located in the cache gallery.
A = The sum of all digits in the total number of panels
B = The number of letters in the artist's last name MINUS the number of letters in the artist's first name
C = The number of holes in the art piece
D = The number of barred windows located totally within the mural TIMES 2
E = The most frequent digit in the address
F = The second digit in the address
CHECKSUM: A + B + C + D + E + F = XY; X + Y = 2
Good luck and enjoy!