Decomposing - When plants and animals die, they decompose. This process uses up oxygen and releases carbon dioxide. Rusting - This is also called oxidation. When things rust they use up oxygen.
I think the correct answer from the choices listed above is option D. The model of the universe that suggests that the sun is the center of the universe was first brought by Copernicus. His model is known as the "Sun centered model".
To solve this problem we will apply the definitions given in Newtonian theory about the Force of gravity, and the Force caused by weight. Both will be defined below, and in equal equilibrium condition to clear the variable concerning acceleration due to gravity. Finally, with the values provided in the statement, it will be replaced.
The equation for the gravitational force between the Earth and the object on the surface of the Earth is

Where,
G = Universal gravitational constant
= Mass of Earth
= Distance between object and center of earth
= Mass of Object
The equation for the gravitational pulling force on the object due to gravitational acceleration is

Equation the two expression we have


This the acceleration due to gravity which is composite constant.
Replacing with our values we have then


The value of composite constant is
. Here, the composite constant is nothing but the acceleration due to gravity which is constant always.
Opposite to the direction of the velocity which led it to its current position.
Explanation:
The direction of momentum when a vertically oscillating block comes to the rest momentarily will be opposite to the direction of the velocity that it has just followed to reach reach its current position.
The direction of change in momentum at the bottom will be upwards and at the top will be downwards.
The change in momentum is mathematically defined as:

where:
mass of the block
final velocity of the block
initial velocity of the block
When the block comes to rest it is due to the result of continuously decreasing velocity.