Question

It was a dark cloudy night. Dhondiba, a farmer wanted to Visit his  field. His educated son was with him. He was a science teacher. Suddenly Dhodiba saw many bats were flying. He was astonished how those bats could see their way in the dark also. His son explained the reason. Can you explain the reason?

Answer 1

Suppose there are 2 bats that can see with their both eyes. 
This means you already got 2 bats who can see with left and 2 who can see with right. 
Suppose there is 1 bat with a good left eye, but a bad right eye. 
We now have: 
2 bats who can see out of their right eye
3 bats who can see out of their left eye
1 bat who cannot see out of his right eye 

Now suppose there are 4 bats who are entirely blind. 
We now have: 
2 bats who can see out of their right eye
3 bats who can see out of their left eye
1 + 4 bats who cannot see out of their right eye
4 bats who cannot see out of their left eye 
This means the minimum of bats is 7.

Answer 2

Hi friend here is your answer.....

Bats are nocturnal animals that have a large number of rod cells responsible for intensity of light in their retina which help them see propeely during the night when there is not much light...
Hope it helps u dear