Our product and our sum always give the same answer. Who are we?

A man is found dead with a knife in his back When the investigation is done. A chair lays beside him and the forensic team finds moisture around the body.

If he committed suicide, how did he do it?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

0 0 0 = 6
1 1 1 = 6
2 2 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

You can use any mathematical symbols in the space provided to make all above algebraic expressions true.

Can you count the number of triangles in the picture below?

A man calls his dog from the opposite side of a river. The dog crosses the river without a bridge or a boat and manages to not get wet. How is this possible?

Can you count the number of matches in the picture below ?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?