What work can one never finish?

Find the next number in the series below

21 32 54 87 131 ?

In the given picture, in how many ways can you read the word "Tiger"?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

I am lying and I always lie. Tell me whether I am lying or telling the truth.

Eight of us go fourth, not back, to protect our king from an attack. What are we?

A boy was driving a car, a girl took a lift from her. She asked his name. The boy said - my name is hidden in my car’s number, find it if you can. After this, she got down Car number was [ WV733N ] Can you guess the name now?

Christina is practising her dance steps along with her friends. In a particular sequence, all of them form a row. At that point, Niharika is standing in the 4th position from either end of the row.
Can you find out how many girls are practising together?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

Use the digits from 1 up to 9 and make 100.

Follow the rules.
=> Each digit should be used only once.
=> You can only use addition.
=> For making a number, two single digits can be combined (for example, 4 and 2 can be combined to form 42 or 24)
=> A fraction can also be made by combining the two single digits (for example, 4 and 2 can be combined to form 4/2 or 2/4)

Question: how can we do this?