Answer:

Explanation:
according to snell's law

refractive index of water n_w is 1.33
refractive index of glass n_g is 1.5


now applying snell's law between air and glass, so we have


![\beta = sin^{-1} [\frac{n_g}{n_a}*sin\alpha]](https://tex.z-dn.net/?f=%5Cbeta%20%3D%20sin%5E%7B-1%7D%20%5B%5Cfrac%7Bn_g%7D%7Bn_a%7D%2Asin%5Calpha%5D)
we know that 

The thin atmosphere of Mars is thought to be due to the planet's lack of a magnetic field, which has allowed the Solar wind to blow away much of the gas the planet once had. Venus, despite still having a thick atmosphere of CO2, surprisingly has a similar problem
Surface tension can change with the change in a medium that is just above the layer of the liquid's surface.
Explanation:
Pouring any oil or oily compounds (such as kerosene) on the free surface of the water will reduce the surface tension.
in the atmosphere directly affects the surface tension of the liquid.
If we increase the temperature of the water, then there is a high possibility of the surface tension of the water getting reduced, due to the fact that the net force of attraction is decreased.
Mixing surfactants or emulsifiers into the water will decrease the surface tension.
If the water is subjected to electrification, then the surface tension will be reduced.
Free fall means rapid fall or a downward motion due to gravity. Sentence example: When Joe was accidentally bumped by Sarah, he was sent towards a free fall down the escalator, leading to a serious injury on his arm and two legs.
B) equal in magnitude but opposite direction