Can you place six X (crosses) in below board without making three in a row in any way ?

Using the clues below, what four numbers am I thinking of?

The sum of all the numbers is 31.
One number is odd.
The highest number minus the lowest number is 7.
If you subtract the middle two numbers, it equals two.
There are no duplicate numbers.

John is asked to stand behind Jacob and Jacob is asked to stand behind John. Both of them feel confused about it and don't know what to do?

But it is quite possible, do you know how?

A worker is to perform work for you for seven straight days. In return for his work, you will pay him 1/7th of a bar of gold per day. The worker requires a daily payment of 1/7th of the bar of gold. What and where are the fewest number of cuts to the bar of gold that will allow you to pay him 1/7th each day?

Identify the hidden meaning behind this picture?

In a jungle where there are no street lights or any other artificial source of lights, I notice a black snake crossing the road.
How did I get sight of the snake?

Which of the eight images will fill the missing image in the puzzle below?

The current time can be represented by below textual rebus.

0
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B.Sc
LLB

Can you tell us the current time?

What four weights can be used to balance from 1 to 30 pounds?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?