TOO long, that is why you should use paper or re-use a glass plate
Styrofoam is not digestible. The body will eliminate it before it would be digestible. Styrofoam should not be consumed under any circumstances.
500 years
400 YEARS.... !
It will take 400 years.
It takes around 12,000 years
Yes, but it can take more than 1 million years, so might as well not use it.
It's best to use a styrofoam container with a lid. Styrofoam will not get as hot as glass or plastic.
It never will. It can be crushed, bent, torn or burned, but it will never decompose. A thousand years from now they will dig up the cans and think they were for something else than for a drink.
Styrofoam is not renewable. It is plastic, made from oil, a fossil fuel. Plastics can be recycled but recycling of domestic styrofoam is often difficult as many recycling plants will not take it.
Depends on what kind of paint, -you didn't say.
2 months
An oceanic plate went underneath a continental plate and so the volcano was formed