To solve this problem it is necessary to use the concepts related to Snell's law.
Snell's law establishes that reflection is subject to

Where,
Angle between the normal surface at the point of contact
n = Indices of refraction for corresponding media
The total internal reflection would then be given by





Therefore the
would be equal to



Therefore the largest value of the angle α is 30.27°
Explanation:
d) Magnetic force is the power that pulls materials together (magnet e. g iron)
an example :how magnet can pick up a coin.
e) frictional force produces when two surfaces are in contact with each other.
effects of friction : I) it produces heat
II) it causes loss in power.
What’s the question so that i can help you
1)

<Solve using the formula which is:
Mass=Density×Volume

2)
3)

(Length × Width × Height)


(Answer=7.5)