Can you answer these questions?

I have questions for you,
questions that I didn’t think I knew.
Start with this one, If poison expires,
will it be more or less poisonous and why?

Oxygen can possibly kill people.
It just takes 80+ years to work, is this possible?
If you try to clean something,
you make something else dirty, isn’t it interesting?

100 years ago, only rich ones owned a car, you see.
Everybody else owned a horse, believe me.
But right now the opposite is true.
Why is it? That’s another question for you.

The questions of what, where, and when.
If you replace ‘w’ with ‘t’, the answer is that, there, and then.
At a movie theatre, when the line of sight is poor,
I am always confused, which arm rest is mine or yours.

If people evolve from monkeys, why are monkeys still around?
If you can give me this answer, you will make me proud.
The last question, I didn’t have an answer, I confess.
Who knew what time it was when the first clock was made.