Solution:

This picture comprises of 31 hands and 155 fingers.

Solution:

Look at her hand. She has five fingers besides the obvious thumb that is not visible. This is not possible and that is what is wrong with the picture.

Solution:

Now there can be two solutions to the given situation because there can be two situations:
Suppose if B and C have same colors, A will know that his color is the other one and he will be able to speak up the first.
Now if B and C do not have same colors, A will stay silent. This will tell B that his and C's colors are different. Thus he will speak up first.

So either A or B will speak up first depending on the situation.

Solution:

Diwali was celebrated as a mark of Lord Krishna win over the Narakasuna by killing him. Now Krishnavathaar comes after Raamavathaar in the Dasavataar. Therefore, Lord Rama could not have celebrated Diwali.

Solution:

We have moved the two matchsticks colored in purple and now the resultant figure contains five 1x1 squares, one 2x2 square and one 3x3 square.

Solution:

Rhea will open just one present.
Cindy|Y - Y is the 25th alphabet
Duk|E - E is the 5th alphabet
Joh|N - N is the fifteenth alphabet
Rhe|A - A is the first alphabet

Solution:

Need for Speed.

Explanation:
Clearly, ds/dt refers to speed. Concluding with whats written already, the movie name is Need for Speed.

Solution:

It was easy as it was daytime. They did not need headlights or the light on the number plate.

Solution:

19|9|9

Explanation:
This is simple. All the months have been coded with a distinctive way.
Let's see about January:
January = 1071 = 10|7|1
10 is the position of J, the first letter of January in alphabetical order.
7 is the number of letters used in forming the word January.
1 is the position of January in the calendar.

For February:
February = 682 = 6|8|2
6 is the position of F, the first letter of February in the alphabetical order.
8 are the number of letters used in forming the word.
2 is the position of February in the calendar.

Similarly, September = 19|9|9
19 is the position of S, the first letter of September in the alphabetical order.
9 are the number of letters used in forming the word.
9 is the position of September in the calendar.

Solution:

It is a baby's face as you can see in the answer picture.