Asoccer ball is sitting in the middle of a soccer field during a game. when the referee blows his whistle, one of the players runs toward the ball and kicks it as hard as he can. the ball flies toward the other team's goal at a rate of about 55 miles per hour. at what rate is the ball moving just before the player kicks it?

Light from a sodium lamp passes through a diffraction grating that has 1000 slits per millimeter. the interference pattern is viewed on a screen 1.000 m behind the grating. the first (m = 1) two bright yellow fringes that are visible are 0.7288 m and 0.7300 m from the central maximum. what are the wavelengths of these two fringes?