$A$ ball is dropped from a spacecraft revolving around the earth at a height of $120 \ km$. What will happen to the ball?

Given below are two statements:
Statement $I$: $A$ satellite is moving around the Earth in an orbit very close to the Earth's surface. The time period of revolution of the satellite depends upon the density of the Earth.
Statement $II$: The time period of revolution of the satellite is $T = 2\pi\sqrt{\frac{R_e}{g}}$ (for a satellite very close to the Earth's surface),where $R_e$ is the radius of the Earth and $g$ is the acceleration due to gravity.
In the light of the above statements,choose the correct answer from the options given below:

If a satellite is orbiting the earth very close to its surface,then the orbital velocity mainly depends on

If the mass of a satellite is doubled and the time period remains constant,the ratio of the orbital radii in the two cases will be:

If the escape velocity of a body from the surface of the earth is $11.2 \,km \,s^{-1}$, then the orbital velocity of a satellite in an orbit which is at a height equal to the radius of the earth is

$A$ satellite is to be placed in an equatorial geostationary orbit around the Earth for communication.
$(a)$ Calculate the height of such a satellite.
$(b)$ Find out the minimum number of satellites that are needed to cover the entire Earth,so that at least one satellite is visible from any point on the equator.
Given: $M = 6 \times 10^{24} \ kg$,$R = 6400 \ km$,$T = 24 \ h$,$G = 6.67 \times 10^{-11} \ N \cdot m^2/kg^2$.