Please help me solve this equation

-85

Step-by-step explanation:

We are given the equation and are asked to evaluate it.

This can be solved using the geometric sequence, but first we have to determine our "r", "n", and .

Of course is equal to 1. Therefore,

= 1

(-2) is the change per number in the sequence, therefore -2 is our "r".

= 1

The number "8" on represents the "n". Therefore 8 is our "n".

Use the geometric sequence sum formula and substitute :

To modify the density of materials present on earth ( A )

Step-by-step explanation:

The collisions of dust, rock and ice causes the modification of the density of materials present on earth, this collision caused the temperature of the earth to rise very high and therefore causing the the earth to melt under such high temperature.

The parts of the earth that was denser than the others after the melting settled down and formed the earth's core while the less denser materials formed the crust of the earth. all the process contributed in the formation of the earth.