You need to arrange three 7 and mathematical symbols to form number 1?

An artist while painting a scenic beauty, decides to paint three layers of blue colour on the sky.

Which layer will go on the first?

A time long back, there lived a king who ruled the great kingdom of Trojan House. As a part of the renovation of the kingdom to meet future security needs, he asked his chief architect to lay down a new play in a manner that all of his 10 castles are connected through five straight walls and each wall must connect four castles together. He also asked the architect that at least one of his castles should be protected with walls. The architect could not come up with any solution that served all of King's choices, but he suggested the best plan that you can see in the picture below. Can you find a better solution to serve the king's demand?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

Can you figure out the logic I used to decide the order of the following words:
gun, shoe, spree, door, hive, kicks, heaven, gate, line, den

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

What building has the most stories?

What is always in front of you but can’t be seen?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?