Can you solve it? The enigma of Randall Munroe

And an intersection of squares

UPDATE: The solutions are up

Today's first puzzle was penned by Randall Munroe, cartoonist of the webcomic xkcd and author of the bestselling book What If?

For the (surely) very few readers who have never heard of him, Munroe, a former NASA roboticist, is probably the world's premier science humorist.