If all Goats are Sheep and all Sheep are Deers, are all Deers Goats ?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Alex is stranded on an island covered in forest.
One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process.

There are cliffs around the island, so he cannot jump off.

How can the Alex survive the fire? (There are no buckets or any other means to put out the fire)

What 5-letter word typed in all capital letters can be read the same upside down?

What have one eye but still cannot see?

What has many keys but can’t open a single lock?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

I never was there, I am always to be.
You have never ever seen me, not ever you will.
Yet I am the confidence of everyone.

Who Am I?

A man has to get a fox, a chicken, and a sack of corn across a river.

He has a rowboat, and it can only carry him and one other thing.
If the fox and the chicken are left together, the fox will eat the chicken.
If the chicken and the corn are left together, the chicken will eat the corn.

How does the man do it?

If you drop a 15 kg iron bar and a 5 kg bag of cotton from a height of 50 meters which will reach the ground first?