Yes
Yes, you can mix conventional oil with synthetic oil with no problem.
It is a gas/oil mix motor, you don't change the oil.
Nothing happens, they just mix. You can buy "blended" motor oil.
Motor oil is insoluble in water and it is denser in water. Therefore, motor oil will not mix with water. It will remain separate.
Yes, and you can even mix them together.
yes very
No, you can even mix synthetic with conventional oil. It will do no harm at all.
That's okay.
No, you must use 2 cycle oil for the mix with gasoline.
The oil mixture for that motor is 1 pint of oil to 6 gallons of gas
it is recommended for all fuel oil mix to be 50:1
They will mix together, but only use it in an engine if it is an approved combination of oil according to the manufacturer.