Yes it will not.cause harm but you , might want to check the blend . Meaning that you may want to see if you are doing a 50/50 blend Ect
That's okay.
No, you can even mix synthetic with conventional oil. It will do no harm at all.
Nothing happens, they just mix. You can buy "blended" motor oil.
Yes, you can. It is even sold as a Synthetic Blend.
Yes.
No. It will ruin an engine. The above answer is 100% wrong. You can mix convention oil with synthetic and it will do no harm at all. When you see them selling Synthetic blend that is what you are buying. A blend of synthetic and conventional oil.
It might be... It's highly not recommended to mix regular and synthetic oils.
Absolutely not. Ignore anyone who tells you different.
Yes
Yes but once you do there is no turning back and no mixing regular motor oil ever again with the synthetic oil....only straight synthetic....or use semi synthetic....now that can be mixed with regular motor oil in a pinch.
Yes, and you can even mix them together.
Yes, you can even mix them.