A magnet’s force is more powerful at its

Explanation: The field of a magnet is strongest at either pole of the magnet. it's equally strong at the North Pole when put next with the South Pole. The force is weaker within the middle of the magnet and halfway between the pole and also the center.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.