Which statement about electric and magnetic fields is true

a. electric fields must leave a positive charge and end on a negative charge

b. electric fields and magnetic fields start at a positive and end at a negative.

c. magnetic fields must start at the north pole of a magnet and end at the south pole of a magnet.

d. electric fields loop from south to north

Which of the following exists around every object that has mass?

A.

a magnetic field

B.

magnetic poles

C.

a gravitational field

D.

electric charges

Explanation:

coil wire, increase current, put iron inside the coil

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.