Questions

GUI stands for Graphical User Interface.

A Graphical User Interface is a computer interface that allows users to interact with a device through graphical elements such as pictures and animations, as opposed to text-based commands.

From the hints,

Only two options for 1st and 2nd digits => 4,2 and 9,3 since it is single digits

Sum of second and third digit  = 10 

If 2 => 3rd digit = 8

If 3 => 3rd digit = 7

4th digit = 2nd digit + 1 => (2+1 =3) or (3+1 = 4)

Sum of all digits = 30

Let 5th digit be x

=> 1st possibility = 4 + 2 + 8 + 3 + x = 30 => x = 13 (Not possible since it has 2 digits)

=> 2nd possibility = 9 + 3 + 7 + 4 + x = 30 => x = 7

Therefore, the PIN is 93747 

A cup.

How the name changed has so many stories. One of them is

In the beginning, Mahabharata has 8800 Slokas and after that it reached to 24000 Slokas. And then it was named as The Great Bharata i.e, Mahabharata.