I think the answer is d. In the magnetotail. I hope this helps! :)
Answer:
0.47 N
Explanation:
Here we have a ball in motion along a circular track.
For an object in circular motion, there is a force that "pulls" the object towards the centre of the circle, and this force is responsible for keeping the object in circular motion.
This force is called centripetal force, and its magnitude is given by:

where
m is the mass of the object
is the angular velocity
r is the radius of the circle
For the ball in this problem we have:
m = 40 g = 0.04 kg is the mass of the ball
is the angular velocity
r = 30 cm = 0.30 m is the radius of the circle
Substituting, we find the force:

Answer:
The change in volume is 
Solution:
As per the question:
Coefficient of linear expansion of Copper, 
Initial Temperature, T =
= 273 K
Final Temperature, T' =
= 273 + 100 = 373 K
Now,
Initial Volume of the block, V = 



where
V' = Final volume


<span>Active Galactic Nuclei.</span>