Answer:The magnetic field around an electromagnet is just the same as the one around a bar magnet. It can, however, be reversed by turning the battery around. Unlike bar magnets, which are permanent magnets, the magnetism of electromagnets can be turned on and off just by closing or opening the switch.
Answer:
d.100 meters
Explanation:
The diameter of the Milky Way Galaxy is approximately 100,000 light years.
Here we are using 1 millimiter (1 mm) to represent 1 light-year (1 ly). So, we can set the following proportion:

and by finding x, we find the diameter of the Milky Way Galaxy in the scale used:

so the correct answer is
d. 100 meters
C is the right image for that biological process.