I've blurred out a word in the title, "2880 _______". What is the missing word?
Hint
When I saw this sculpture for the first time, I stopped and counted how many elbow pipes were used in its construction, and I was quite pleased to confirm that the title was accurate.
Can you identify seven eight U. S. states from close-ups of their state quarters and license plates? (Each of #1–6 has a single answer, but the quarter and license plate in #7 are from different states, despite depicting the same object.)
Solution
Congratulations to yesterday's partial solvers Natalie, Inca, Charlie, Jacob C., and Connor, and complete solvers Graham, Kate, and the Greggs. Thanks to everybody who made a guess!
Ten years later, Dr. Shapiro revived Puzzle of the Day at Proof School, writing each day's puzzle on a name tag. After 600 puzzles or so, he was just starting to feel normal about students reading his chest all the time when campus closed and the puzzle, like the rest of our lives, moved online. New puzzles are posted daily on school days.
Want to catch up on old PotDs? There's an archive currently containing puzzles from March 2020 to March 2021.