To solve this problem it is necessary to apply the concepts related to the electric field according to the definition of Coulomb's law.
The electric field is defined mathematically as a vector field that associates to each point in space the (electrostatic or Coulomb) force per unit of charge exerted on an infinitesimal positive test charge at rest at that point.
Mathematically this can be described as:

Where,
permittivity of free space
r = Distance
q = Charge
E = Electric Field
Our values are given as,



Replacing we have,




Therefore the amoun of charge on the outer surface of the larger shell is 
Translation of important question part (Google translation used)
Force of 6N causes a displacement of 0.03m. remove the balance and connect a body 0.5 kg to the end, pull it to move it 0.02 m, release it and see how it oscillates.
(a)Determine the spring constant.
(b)Calculate angular velocity, frequency, and oscillation period
Answer:
(a)K=200 N/m
(b) w= 20 rad/s f=3.2 Hz T=0.3125 s
Explanation:
(a)
From Hooke's law, we deduce that F=kx where F is applied force, k is spring constant and x is extension of the spring. Making k the subject of the formula then k=F/x and substituting F with 6 N and x with 0.03 m then k=6/0.03=200 N/m
(b)
Angular velocity, w is given by
where m is the mass and k is spring constant calculated in part a above. Substituting mass with 0.5 kg and k with 200 N/m then

We know that frequency, f is given by
and substituting 20 rad/s for w then
Finally, oscillation period, T is usually the reciprocal of frequency hence T=1/f and substituting f with 3.2 Hz then T=1/3.2=0.3125 s
Answer:
E) linear motion; otolith organs 100%
Explanation:
Since the Units presented are not in the International System we will proceed to convert them. We know that,

So the speed in SI would be


The change in frequency when the wave is reflected is

Or we can rearrange the equation as

f' = Apparent frequency
f = Original Frequency
c = Speed of light


Replacing,


Since the waves are reflected, hence the change in frequency at the gun is equal to twice the change in frequency



Therefore the increase in frequency is 2979.63Hz
Explanation:
The total resistance used to calculate the total resistance of the two parallel resistor is given by :

Taking reciprocal of the above equation.

We can also write the above equation as :

On simplification of above equation,

or

Hence, proved.