What is the next number in this matchsticks series riddle?

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.

Can you replace the question mark with the correct number in the below table sequence?

You are mixing a mixture of cement and Sand with five gallons of water. You have a garden hose giving you all the water you need. The problem is that you only have a four-gallon bucket and a seven-gallon bucket and neither has graduation marks. Find a method to measure five gallons.

"That Restaurant always remains crowded. This is the reason why nobody goes there".

Can you find a flaw in this statement?

If two's company, and three's a crowd, then whats four and five ?

With pointed fangs I sit and wait; with piercing force I crunch out fate; grabbing victims, proclaiming might; physically joining with a single bite. What am I?

Count the number of triangles in the picture below:

The answer I give is yes, but what I mean is no. What was the question?

I know a country, If you remove the last alphabet of its name, it will become a part of your body. Do you name it?