Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Write the next letter in this sequence.
O, T, T, F, F, S, S, E, __
**Hint: It is a Number Series Puzzle

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

I am first found in caves, now prolific online; I am a depiction, a drawing, a symbol, or sign. I will convey whichever mood you could wish; or for that matter, a fist, flask, or fish. What am I?

I am quite hot but become too cold if you remove the first two letters. What am I?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

What is the next number in the series?

15 29 56 108 208 ?

There is a box. The area of its top is 240 square units, the area of the front is 300 square units and the area of the end is 180 square units.

Can you calculate the dimensions of this box with the given data?

Optical Illusion Eye Test: You Have A Brain Like Computers If You Can Spot Two B's Among R's In 8 Seconds!

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different. How do you measure 45 minutes?