How many yards is the penalty for unnecessary roughness?

How long is each quarter in an NFL game? How many timeouts does each NFL team get per half? How many yards is the penalty for a false start? How many yards is the penalty for holding by the offense? How many teams are in the NFL? What are the two conferences of the NFL called? How many divisions does each NFL conference have? What is the position of the player who snaps the ball to the quarterback?