Solution:

89 (ASCII CODE OF Y)

Q W E R T Y
81 87 69 82 84 ?

Solution:

I am surrounded by the enemies.

Solution:

They are sunglasses (sit on the bridge of your nose)

Solution:

35

Explanation
4 : 1/2 X 1/2 matchsticks squares
17: 1X1 matchsticks squares
9 : 2X2 matchsticks squares
4 : 3X3 matchsticks squares
1 : 4X4 matchsticks squares
================
35

Solution:

There can be various solutions. Here are a few that we came up with: 1 + 2 + 4/6 + 5 + 7/3 + 89 = 100
12 + 6/3 + 75 + 8/4 + 9 = 100
1/6 + 2 + 4/8 + 7/3 + 95 = 100
24 + 57 + 6/3 + 8 + 9/1 = 100
36 + 4/8 + 51 + 7/2 + 9 = 100
3/2 + 5 + 6/8 + 7/4 + 91 = 100

Solution:

Over My Dead Body

Solution:

f the last elf is taking some time to answer the question then it shall mean that the elf's before him are all wearing distinct coloured hats. However sufficient time shall be given to the last elf to give the answer.
If he views the similar coloured hats in front of him , he shall quickly tell the answer

Solution:

In the corners of the square, tighten two ropes. Tighten another rope between them by putting rings on each rope. That rope should be tightened on the sheep's neck on the other end.

Solution:

11

Solution:

India has the highest chances of winning the war (47/90)
Missile Firing order:
Chances of Remaining Unhit - Pakistan:
Chances of Remaining Unhit - Srilanka:
Chances of Remaining Unhit - India

Pakistan - Srilanka - India
1/2 0 1/2

Pakistan - India - Srilanka
1/2 0 1/2

India - Pakistan - Srilanka
1/10 16/45 49/90

Srilanka- Pakistan - India
1/2 0 1/2

Srilanka - India - Pakistan
1/10 16/45 49/90

India - Srilanka - Pakistan
1/10 16/45 49/90

Total chances of being unhit (sum of the probabilities divided by 6):
27/90 16/90 47/90