Answer:
1:Gravity acts on all masses equally, even though the effects on both masses may be different because gravity causes all objects to fall at the same constant rate of 9.8 m/s2. An object in free fall means that the only force acting on the object is gravity
2:Our universe began with an explosion of space itself - the Big Bang. Starting from extremely high density and temperature, space expanded, the universe cooled, and the simplest elements formed. Gravity gradually drew matter together to form the first stars and the first galaxies.
3:A scientific theory is an explanation of something in the natural world that is based on past observations and evidence.
4:In biology, cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells.
Explanation:
