Template:Are You Sure/March 2

• ... that mathematician Jordan Carson Mark oversaw the development of nuclear weapons for the US military, including the hydrogen bomb in the 1950s; and that Mark was able to bring together experts like Edward Teller, Stanislaw Ulam, and Marshall Holloway despite their personal differences?

• ... that a semaphore telegraph is a system of conveying information by means of visual signals, using towers with pivoting shutters, also known as blades or paddles?

• ... that George Gershwin's I Got Spaces is a tribute to spaces, vectors, metrics, and other mathematical objects?