Why is a magnetic field a vector quantity?
a.
directional force
b.
directional speed
c.
specified location
d.
it produces long field lines.
e.
it produces field lines that are close together.

A magnetic field  is a vector quantity because of directional force.

Option A

Explanation:

The magnetic field at any case is a vector quantity as it has both magnitude and direction. A magnetic field has a direction associated with a field as well as the strength of the field. The magnetic field is the space that the magnet creates around itself and is hence a vector quantity as it can be experienced. The S.I. unit of magnetic field is Tesla. It is to be noted that a magnetic field always contains strength.

thermal energy is the answer

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