In which of the following scenarios is the greatest amount of work accomplished?
1)a girl weighing 70 n goes up a flight of stairs that is 4.0 meters high carrying a box that weighs 2.0 n.
2)a girl weighing 55 n goes up a flight of stairs that is 2.5 meters high carrying a box that weighs 1.0 n.
3)a girl weighing 60 n goes up a flight of stairs that is 3.0 meters high carrying a box that weighs 1.5 n.
4)a girl weighing 80 n goes up a flight of stairs that is 5.0 meters high carrying a box that weighs 0.5 n.

Work done is product of force and displacement

so maximum work is done in

4)A girl weighing 80 N goes up a flight of stairs that is 5.0 meters high carrying a box that weighs 0.5 N.

Explanation:

lets discuss all given cases

1)A girl weighing 70 N goes up a flight of stairs that is 4.0 meters high carrying a box that weighs 2.0 N.

here total force = 70 + 2 = 72 N

height = 4 meter

2)A girl weighing 55 N goes up a flight of stairs that is 2.5 meters high carrying a box that weighs 1.0 N.

here total force = 55 + 1 = 56 N

height = 2.5 meter

3)A girl weighing 60 N goes up a flight of stairs that is 3.0 meters high carrying a box that weighs 1.5 N.

here total force = 60 + 1.5 = 61.5 N

height = 3.0 meter

4)A girl weighing 80 N goes up a flight of stairs that is 5.0 meters high carrying a box that weighs 0.5 N.

here total force = 80 + 0.5 = 80.5 N

height = 5 meter

So maximum work in done in case 4