I skipped the 1965 march question because I didn't know what MLK stood for. After I saw the answer, I thought, isn't that the place where Martin Luther King marched? Then I realised.
I took three years of math in high school (and hated every minute of it) and my college degree is in a social science. I still never heard of Euler, but I just looked him up and yes, he was impressive.
Or... done math and not the history about it.. I don't remember any history classes in any of my math classes (elementary/middle/high school or university)
Why is Euler clued with a question mark? Maybe my crosswords are leaking into Jetpunk but that had me looking for a somehow punny answer that wasn't an actual mathematician. If it's just to convey doubt, "possibly the greatest mathematician ever" would be better.