Which of the following statements are true?
check all that apply.
a) a time-varying electric field will produce a magnetic field.
b) electric and magnetic fields can be treated independently only if they vary in time.
c) time-varying electric and magnetic fields can propagate through space only if there is no matter in their path.
d) a time-varying magnetic field will produce an electric field.

A) A time-varying electric field will produce a magnetic field.

D) A time-varying magnetic field will produce an electric field.

Explanation:

As we know that time varying electric field can induce displacement current in the space

So we will have

now we have

so it will induce magnetic field given as

Now similarly time varying magnetic field can induce electric field by Faraday's law given as

now we have

so we have

so induce electric field is due to magnetic field

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.

i think the answer is a, hope this : )