Can you name four days which start with the letter 'T'?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

I am white when I am dirty, and black when I am clean. What am I?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

When 99 is considered higher than 100?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

A beggar on the street can make one cigarette out of every 6 cigarette butts he finds. After one whole day of searching and checking public ashtrays the beggar finds a total of 72 cigarette butts. How many cigarettes can he make and smoke from the butts he found?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

When we see 2 but call 10?