A construction worker uses a board and log as a lever to lift a heavy rock. He applies a force of 20 without the use of the lever, however with the lever, he applies a force of 10 N. What is the mechanical advantage

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