Answer:
A difference between of echo and reverberation is described below in details.
Explanation:
Here's a piece of immediate information: An echo is an individual consideration of a soundwave off a horizon exterior. Reverberation is the consideration of sound waves generated by the superposition of the before-mentioned echoes. ... A reverberation can happen when a sound wave is displayed off a nearby covering.
Answer:
995 N
Explanation:
Weight of surface, w= 4000N
Gravitational constant, g, is taken as 9.81 hence mass, m of surface is W/g where W is weight of surface
m= 4000/9.81= 407.7472
Using radius of orbit of 6371km
The force of gravity of satellite in its orbit, 
Where
and 

F= 995.01142 then rounded off
F=995N
Not sure.can you give me a clue?
Answer: 3.92 N.
Explanation:
Your box weighs 400g, or 0.4kg. In order to lift it, you need to overcome the force of gravity. F = ma, and acceleration due to gravity is -9.8 m/s^2. So gravity acts on the box with a force of 0.4 kg * -9.8 m/s^2 = -3.92 N. A force of +3.92 N is required to overcome this.