Light travels at a constant speed of about 300,000 km/s. this speed is referred to as the speed of light. a light year is the distance that light travels in one year. one light year is equal to 9.46 trillion kilometers. the closest star to earth, other than the sun, is proxima centauri. it takes light from this star about 4.2 years to reach earth. how far from earth is the star proxima centauri? a. 4.2 light years b. 9.46 trillion km c. 300,000 light years d. 300,000 km.

Based on the information in the question, a light year is the distance traveled light in one year. Then if the light from the star Centauri takes 4.2 years to reach the earth, then its distance from earth is 4.2 light years.

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