Lost at Sea: The Search for Longitude

"It must be...

B.) ...Chicago!" (longitude: about 88 degrees west)
That would have been some trip - across the Atlantic, up the St. Lawrence River, through the Great Lakes - but it's not correct, anyway. Remember, it's noon on the boat (the sun is directly overhead), 4:40 p.m. in Greenwich, and the Earth rotates from west to east 15 degrees each hour or 5 degrees every 20 minutes. So re-check your math, and try again.

"Surely, it's...

A.) Havana!" (longitude: about 82 degrees west of Greenwich)
B.) Chicago!" (longitude: about 88 degrees west)
C.) Tashkent, Uzebekistan!" (longitude: about 70 degrees east)
D.) Cape Cod!" (longitude: about 70 degrees west)