A cement block accidentally falls from rest from the ledge of a 55.2-m-high building. When the block is 12.2 m above the ground, a man, 1.80 m tall, looks up and notices that the block is directly above him. How much time, at most, does the man have to get out of the way

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

it is a negative acceleration