If 21x = 79x, what is the value of x?

In the four images below, can you find the odd one out?

Can you identify the hidden rebus in the image below?

A sea diver is a real show-off. He showed everyone that he can hold his breath underwater for 15 minutes.

I went to the diver and told him that I can be underwater for double the time i.e 30 minutes.
He responded that he will give me 100$ if I would be able to do it. I won 100$.

What did I do?

What is the word or phrase below?
R | E | A | D

What have one eye but still cannot see?

What demands an answer, but asks no questions

Once upon a time, there was a castle on a square island. The entire island was surrounded by a 14m wide trench. The Romans had wanted to invade the castle and had brought a few wooden planks along with them to facilitate themselves in crossing the moat. The planks were however found to be only 13m long.

The Romans still managed to cross the trench. How did they do it?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?