Can you fill the blank with the correct number?

6 30 870 756030 _____

How many triangles can you count in the figure given?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

Bopanna was working on a murder case when he received a message about the location of the murder weapon.
The message was encrypted as below.

"deb mitciv eht edisni neddih si nopaew redrum ehT"

Tell me the location of the murder weapon.

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

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

Which is the rope you never skip with?

What goes up but never comes down?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?