Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Replace the question mark with the number below given a simple math problem.

15 caves are arranged in a circle at the temple of doom. One of these caves has the treasure of gems and wealth. Each day the treasure keepers can move the treasure to an adjacent cave or can keep it in the same cave. Every day two treasure seekers visit the place and have enough time to enter any two caves of their choice.

How do the treasure seekers ensure that they find the treasure in the minimum number of possible days?

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?

You can hear me, but you can't touch or see me.

What am I?

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

John is the son of Jacob.
So,
Jacob is the_____of John's father?