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
Answer:
Albert Einstein was from Germany he was born theoritical physicist, from childhood only he loved mechanical toys, he was highly gifted in Mathematics, He was a world citizen and a scientific genius too. His contribution were:
1) he developed the theory of relativity
2) he also discovered the process of nuclear fission
3)he developed the quantum theory of specific heat
4)theory of stimulated emission, on which laser device technology is based
5) law of photoelectric effect
hope it helped you :)