Solution:

The ten difference are as follows:
1) The direction of the paper plane is changed.
2) The amount of white flowers is different.
3) There is one extra bird.
4) The shoes of the girl are plain white.
5) One snail is missing from the picture.
6) There is one extra butterfly.
7) One apple is missing from the picture.
8) Different number of dots of the bow of the girl.
9) There is one extra plant.
10) If you notice, an airplane is missing from the ground.

Solution:

The Password.

Explanation:
Clues 2 and 5 are correct and rest are lies.

Solution:

See the figure for the answer. Wasn't it a bit tricky?

Solution:

Baseball umpire and the Catcher (Eden Hazard was playing baseball.)

Solution:

Put one black rock in one sack and put all the rest in the other one. In such manner you will get about 3/4 probability of surviving.

Solution:

On the back, since bullet train is accelerating, therefore,the person at the back will spend less time than one in front.

Solution:

The attached picture shows you how you can do it. If you were able to deduce any other way, feel free to comment.

Solution:

The numbers that have been written over the calendar are:
12, 4, 8 and 3

A few numbers have been circled under particular months. The curious thing is that the numbers that have been written are the same number of corresponding months under which the dates have been marked.

What we can judge by the overall calendar is that the dates that have been marked may refer to the letters at that position in the month's name. In addition, the written numbers can be the position of those letters. Let's simplify below:

12th month is December
The number marked under December = 5
The fifth letter of December = M

4th month is April
The number marked under April = 4
The fourth letter of April = I

8th month is August
The number marked under August is 6
The sixth letter of August = T

3rd month is March
The numbers marked under March are 4 and 5
The fourth and fifth letter of March = C and H

When you combine the letters, you get the name as MITCH.
Therefore, Mitch is the killer.

Solution:

Take 10 number of cards in a new deck and change their face direction. For example- You create a new deck of 10 cards and out of 10, 3 faces up in the new deck. So remaining 7 faces up are in the old deck. But hey! while creating the new deck you reversed the face direction of new cards. So actually the 3 cards which were facing up are actually face down in the new deck while 7 faces up.

Solution:

888 + 88 + 8 + 8 + 8 = 1000

Solution:

The mules is moving in circular path and hence outside legs travels more distance than inner legs.