I’m tall when I’m young, and I’m short when I’m old. What am I?

Why do we preferably have round manhole covers and not square ones?

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?

Can you solve the photo plexer logic ?

Find out the missing number in the picture attached:

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

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

John went to meet his friend Jacob, but when he was about to reach the main gate, John notices that Jacob had a mighty dog who was fastened to the tree. The chain is long enough that it allows the dog to reach the main gate.

How can the John reach the main gate?

A crime was committed at baker street. Ibrahim Dakota who was shot in the stomach was the main suspect. Sherlock questioned the suspect. The conversation started as:
Sherlock: What's your story, Ibrahim?
Ibrahim: I was walking around baker street and suddenly a man from the back shot me. I ran as fast as I could to save my life".
Sherlock: That is enough (and ask the police to arrest him).

Why does Sherlock think he is the murderer?

2, 3, 5, 9, 17, _ What is the next number in the sequence?