Questions

In the given puzzle the logic is

2 x 1 + 1 = 2 + 1 = 3

3 x 2 + 2 = 6 + 2 = 8

4 x 3 + 3 = 12 + 3 = 15

5 x 4 + 4 = 20 + 4 = 24

6 x 5 + 5 = 30 + 5 = 35

Similarly,

7 x 6 + 6 = 42 + 6 = 48

7 = 48.

In the starting it is given that Couple went to the movie and No other went with them.

So total members went to movie is only 2.

Maulana Abul Kalam Azad, the first education minister of independent India, who served from 15 August 1947 until 2 February 1958.

Indira Gandhi - First Women Prime minister of India

Durba Banerjee - The first woman Airline Pilot

Sucheta Kripalani - The first woman Chief Minister of an Indian State.

Because the refractive index of glass is highest, light travels slowly in Glass. 

We know that the speed of light depends on the refraction index. The higher the index of refraction is, the slower the speed of light is.

R.I of air and vacuum = 0 (air is a teeny bit more but can be taken as 0)
R.I of water = 1.33
R.I of glass = 1.4.

Hence, Light travels slowest in Glass.