There are 8 countries with official ownership and control of atomic bombs: The US, Russia, UK, France, China, India, Pakistan and North Korea. There are 5 countries storing atomic bombs, but with ultimate custody for the bombs belonging to the US: Belgium, Germany, Italy, The Netherlands and Turkey. Israel is also believed to have atomic bombs. And Iran,possibly.
2
As both atomic bombs and supernovas vary in yield, this question has no single answer.
Atomic bombs- Zero.
2
100
More & higher yield atomic bombs, I guess.
Yes, uranium can be used in atomic bombs.
Atomic bombs were dropped in WWII
Many atomic bombs were detonated for "test" purposes. Fortunately none were used in war.
2 atomic bombs and 2 million HE bombs and 5 million incendiary fire bombs
1 WW2 was the only war to detonate atomic bombs. Pray no one ever uses any again.