Gravity is the cause of . . .
-- star formation,
-- planet formation,
-- orbits.
So without gravity, there pretty much wouldn't be any solar or any system.
The acceleration of the particle at time t is:

The velocity of the particle at time t is given by the integral of the acceleration a(t):

and the position of the particle at time t is given by the integral of the velocity v(t):

Assuming the particle starts from position x(0)=0 at t=0, the distance the particle covers in the first t=2 seconds can be found by substituting t=2 s in the equation of x(t):
Answer:
Visible Light and Radio waves
Explanation:
The earth's atmosphere is transparent to a few windows in the electromagnetic spectrum. it is completely transparent to allow observation from the ground in visible light rang 380 to 740 nano meters. Also in the range of radio wave as communication are done from space to ground in the form of radio waves.
it is Partially transparent to Microwave and infrared range.
The answer is Decibels. <span />