You stand on a spring scale on the floor of an elevator. the scale shows the highest reading when the elevator
1. remains stationary.
2. moves upward with increasing speed.
3. moves downward with increasing speed.
4. moves downward at constant speed.
5. moves upward with decreasing speed.

2. moves upward with increasing speed.

Explanation:

When an object it going up in an elevator, the object experiences the upward acceleration as well as the acceleration due to gravity. This means that the object feels that they are being pushed down.

Hence, the scale shows highest reading when the elevator moves upward with increasing speed.

The force on the scale would be

Where,

m = Mass of object

g = Acceleration due to gravity = 9.81 m/s²

a = Acceleration of the elevator

c.is a substance that requires a small amount of energy per gram to raise its temperature; has strong cohesive forces between molecules.

explanation:

a colorless, transparent, odorless liquid that forms the seas, lakes, rivers, and rain and is the basis of the fluids of living organisms.