Which of earth sphere have the most mass

Aforklift raises a 1,020 n crate 3.50 m up to a shelf. how much work is done by the forklift on the crate? the forklift does j of work on the crate.

Suppose you increase your walking speed from 7 m/s to 13 m/s in a period of 2 s. what is your acceleration?

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?