Brian is watching an old game show rerun on television called Let's Make a Deal in which the contestant chooses a prize behind one of two curtains. Behind one of the curtains is a gag prize worth $250, and behind the other is a round-the-world trip worth $8,200. The producer of the game show has placed a subliminal message on the curtain containing the gag prize, which makes the probability of choosing the gag prize equal to 75 percent. What is the standard deviation of that selection? (Round answer to 2 decimal places, e.g. 15.25.) Standard deviation $