Answer:
8) d
9) c
<em>Hope this helps! :)</em>
Answer:
324795 C
252.637820565 N/C

Explanation:
= Permittivity of free space = 
R = Radius of Mars = 
A = Area = 
= Electric flux = 
Electric flux is given by

The charge is 324795 C
Electric field is given by

The electric field is 252.637820565 N/C
Surface charge density is given by

The surface charge density is 
Answer:
1) It must contain large amount of stored energy. So that more amount of power output available to run the engines, motors etc.
2) It must occur in abundance in nature or be easy to produce.
3) The fuel must be made up of ele.
Explanation:
See this image for answer