What goes up but never comes down?

A maths symbol is hidden in the below Bar Graph. Can you decipher it?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

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

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?

Can you find out the remainder when 3^300 is divided by 5?

There is a five-letter word which has 3 consonants(all are same) and 2 different vowels.
Also, something wrong is associated with the word.

Can you name it?

If,

Akriti = 631
Levis = 521
Sroti = 521
Aneel = 533
Then,
Sunil =?

If all the below statements are true

1. Gianni was either in Italy or France in 1997.
2. If Gianni did not kill Versace, Hilton must have killed him.
3. If Versace died of suffocation, then either Gianni killed him or Versace committed suicide.
4. If Gianni was in Italy in 1997, then Gianni did not kill Versace.
5. Versace died of suffocation, but he did not kill himself.

Who killed Versace and where was Gianni in 1997?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?