What you cannot hold but it is yours?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Can you place three balls such that the equation shown in the picture holds true?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

What has many teeth, but cannot bite?

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

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?

Mr Black, Mr Gray, and Mr White are fighting in a truel. They each get a gun and take turns shooting at each other until only one person is left. Mr Black, who hits his shot 1/3 of the time, gets to shoot first. Mr Gray, who hits his shot 2/3 of the time, gets to shoot next, assuming he is still alive. Mr White, who hits his shot all the time, shoots next, assuming he is also alive. The cycle repeats. If you are Mr Black, where should you shoot first for the highest chance of survival?

How many triangles do you see in the picture puzzle below?