1. a ball is dropped from a tower. from whose reference point is the ball approaching the observer?
a)a person standing on top of the tower

b)a person on the ground driving rapidly away from the tower.

c)a person in an airplane flying above the tower

d)a person standing on the ground beneath the tower

Option-(D): The more obvious answer to the question will be,a person standing on the ground beneath the tower.

Explanation:

The observer:

When a ball is dropped from a certain point or height,H it will be perceived differently by a number of people and it will all depend on the position of those individuals inside the specific time frame in which they exists. So, after evaluation of all the options  we get to know that it will be the person who is standing on the ground that will be able to likely observe the event.

specific latent heat of fusion, lf, of a substance is defined as the amount of heat required to change a unit mass of the substance from solid to liquid state, without any change in the temperature.

explanation: