Answer:
a. 
b. 
c. 
d. 
Explanation:
To make analysis about the satellite circular earth the depends or r and A


a.


b.


c.



d.


Answer:
The force is 
The time is 
Explanation:
From the question we are told that
The mass of the car is 
The initial velocity of the car is 
The final velocity of the car is 
The acceleration is 
Generally the acceleration is mathematically represented as

=> 
=> 
converting to seconds

=> 
Generally the force is mathematically represented as

=> 
=> 
Now converting to foot-pound-second we have

=> 
As the plastic sphere is charged, therefore it experience an electric force when placed in an electric fields and also experiences gravitational force acts downward so the electric force must act upward.
Let
is electric force and
is gravitational force.
If these forces are balanced, therefore
or 
Given,
and
.
Substituting these values in above equation we get,

Thus, the magnitude of electric field is
.
As the charge is negative, the electric field at the location of the plastic sphere must be pointing downward.