A child pulling a wagon across the grass but friction between the grass and wheel creates a force in the opposite direction. If the wagon is speeding up, what does that mean about the two forces?

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.