Along, straight wire carries a current i. if the magnetic field at a distance d from the wire has magnitude b, what is the magnitude of the magnetic field at a distance 2d from the wire?

Suppose a soccer ball is kicked from the ground at an angle 20.0º above the horizontal at 8.00 m/s. the y-velocity is determined to be 2.74 m/s. how long will the ball be in the air? assume the ball lands at the same height at which it was kicked.