What is both possible and impossible at the same time?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

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?

The centre of the third figure is empty. What digit should fit inside?

who is silent in the parliament?

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

Women do it once a year after they turn 19 but men get to do it only once in a lifetime. What is it?

If,

6 / 7 = 2
3 / 9 = 7
8 / 2 = 6

Then

4 / 5 = ?

Can you find the company name in the pictogram below?

A man dies of old age on his 25 birthday. How is this possible?