Verified answer

I think that the most likely outcome is that your arm would be ripped clean off. But that depends on the angles.

If you hit it straight on then your arm would crush. The bone broken into 30 or forty pieces a cm or so long.

But you wouldn't feel it at all. "No brain no pain".

Between 6.723 and 7.958 depending on whether your right foot was in the air or on vacation.

It depends...

If they were also leaning out of a car going in the same direction at 99 mph, there wouldn't much difference between this and a regular punch.

Calculations such as this are not dependent on your velocity, but on the velocity difference between you and your target.

As stated, the velocity of the target is unspecified.

and of course you have the relativity formula for that ?

The big question here is what is wrong with you that you are even thinking of things like this?

you would break most of the bones in your hand and wrist, and possibly in your arm.

Your hand would cease to exist.