Approximately 4 billion years.
Atoms or elements can exist in a metastable state, including technetium (Tc), promethium (Pm), and uranium-235(U-235). These isotopes have relatively long half-lives, making them naturally occurring but unstable in the long term.
Yes - butter existed long before the 1930s - it was present long before the middle ages.
You'd probably call it quasi-stable or meta-stable (it will stay put as long as nothing bothers it, but it can easily fall down and enter a more stable state).
It takes about 10 million years for a star like our sun to form and reach its stable state.
4 years - 1784-1788
A stable compound is a chemical substance where the atoms are bonded together in a way that does not easily break apart under normal conditions. It has a well-defined structure and can exist in a relatively unchanged state for a long period of time.
Static Variables are created when the class is loaded and continue to exist as long as the class is loaded/present in the JVM
3 days
Nearly seventy years.
Rome has existed from 753 BC to the present, a time span of 2,764 years.
35,000 years ago until the present. They never died out. Modern Europeans are descended from the Cro-Magnon.
That period varies from state to state. You would need to check the provision of your state laws.