There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Jenifer and Jesica are having a conversation.

Jenifer: I am definitely not over 30.
Jesica: I am 28 and you are surely 5 years older to me at least.
Jenifer: No, you are at least 29.

You are told that both of them are lying throughout in the conversation. Can you find their respective ages?

An evil man kidnapped someone and made them take one of two pills. One was harmless, but the other was poisonous. Whichever pill the victim took, the kidnapper took the other one. The victim took their pill with water and died. The kidnapper survived. How did the kidnapper get the harmless pill?

what one word does the below rebus identifies?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

In my garden, I have many trees but only one of them is the mango tree. In these mango trees, there are some mangoes(as expected).

But after a strong wind, there are neither mangoes on the tree nor on the ground. Explain?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

Buy me, smell me or deliver me, I do not change.

Who am I?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?