What does this simple rebus mean?

Find the next number in the sequence

1, 2, 6, 21, 88, __?

John 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 correct number below.

What has lots of eyes, but can’t see?

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

There is a barrel with no lid and some wine in it. 'This barrel of wine is more than half full,' said Curly. 'No it's not,' says Mo. 'It's less than half full.' Without any measuring implements and without removing any wine from the barrel, how can they easily determine who is correct?

John and Jacob are twin brothers. One of them is a liar whereas the other one is a truth-teller.

I called their home number and one of them picked up.
I asked. 'Does John lie?' The person replied with a yes.

Whom did I talk with, John or Jacob?

Can you count the number of matches in the picture below ?