What occurs twice in a week, once in a year but never in a day?

A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?

Decode this picture on T-Shirt and tell what it says ?

I am written with two letters.
I said with the one.
I usually am seen with the two.

Who am I?

There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?

What seven-letter word has hundreds of letters in it?

Mr Red Lives in the red house.
Mr Green Lives in the greenhouse.
Mr Yellow Lives in the yellow house.

Who lives in the Whitehouse?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

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?