Answer:
A. When it is in a magnetic field, it becomes a temporary magnet.
Explanation:
An iron bolt is attracted to a magnet because when in a magnetic field, the iron becomes a temporary magnet.
This is because the iron aligns their electrons in the magnetic fields.
- This causes that attraction between the magnet and the iron.
- Metals like iron are said to be ferromagnetic
- Unpaired electrons in iron spin in such a way that they align with the magnetic fields of the magnet.
average velocity is vector displacement / time
time is "almost exactly one hour"
disp = -10m
v= -10/1x60x60 = -1/360m/s

Since the diameter of helium atom is approximately
, therefore the diameter of helium atom in nano meter,

Answer:
V=2.8 ml
Explanation:
volume of the cube is it would be 20.3 - 17.5 ml so 2.8 ml.