You can see it everyday, But cannot touch it at will. What is it?

What has one eye, but can’t see?

How many letters are in the alphabet?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

To attend world science seminar, A famous chemist from Mexico visit
London. In the lab, the scientist was killed and his six assistants were under suspicion of killing the chemist.
Name of six assistants: Austin, Wayne, Dege, Oscaru, Lingard, and Rojo.
He left a note "76-20-44 79-16-22-7"

A local detective Jack was called to solve the case,

After reading the note, Jack instantly asked the police to arrest the murderers.

Who are the murderers?

Can you count the number of triangles in the given figure?

In a classic wine shop, the list of three most popular wines are:
- The cost of 1 French wine bottle: 500$
- The cost of 1 German wine bottle: 100$
- The cost of 20 Dutch wine bottles: 100$

John entered the wine shop and he needs to buy
- All three types of wine bottles.
- Needs to buy Dutch wine bottles in multiples of 20.
- Need to buy 100 wine bottles in total.

John has only 10000$. How many wine bottles of each type, John must buy?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

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

How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?