Solution:

A picture of Chimpanzee.

Solution:

C

Explanation:
It Seems, the water level might be even in all the glasses, but what will happened if we remove the objects from the glasses. When you put an object in water, it will displace the water with the mass of the object Hence, the glass that contains the object with the least amount of weight will have the most water in it.

Even though we might not know the exact weight of all those four objects, we can all agree, that the paper clip weighs the least and hence will displace the minimum water.

Solution:

The Numbers IX and XI have switched the places in the watch.

Solution:

6.25

Explanation:
2 1/2 x 2 1/2
= 5/2 x 5/2
= 25/4
= 6.25

Solution:

4th.

Solution:

Potato
Pot + at + to(toe)

Solution:

The cow that stands out is marked. Check the black spots.

Solution:

All other shapes are quadrilaterals, while a hexagon has six sides.

Solution:

The riddle, the 'facts' of which may or may not be true, results in the following equation:

x/6 + x/12 + x/7 + 5 + x/2 + 4 = x

where x is Abhishek's age at the time of his death.

Therefore, salmna lived exactly 84 years.

Solution:

Let the length of the bridge be x meters.
Running towards the train, Charles covers 0.5x-10 meters in the time that the train travels x-4 meters. Running away from the train, Charles covers 0.5x+2 meters in the time that the train travels 2x-8 meters.

Because their speeds are constant, the following holds:

(0.5x-10) / (x-4) = (0.5x+2) / (2x-8)
which can be rewritten to
0.5x2 - 24x + 88 = 0
Using the abc formula we find that x=44, so the railway-bridge has a length of 44 meters.