Answer:
mu=12Tm^2
Explanation:
the magnetic moment mu of a single loop is given by:

where I is the current, B is the magnetic field and A is the area of the loop. By replacing we obtain:

hope this helps!!
Answer: -33.3 * 10^9 C/m^2( nC/m^2)
Explanation: In order to solve this problem we have to use the gaussian law, the we have:
Eoutside =0 so teh Q inside==
the Q inside= 4.6 nC/m*L + σ *2*π*b*L where L is the large of the Gaussian surface and b the radius of the shell.
Then we simplify and get
σ= -4.6/(2*π*b)= -33.3 nC/m^2
It’s the crest, the crest is the top part of the wave and the trough is the bottom so they correspond
The answer to that will be the Troposphere.