What is radioactivity?

What is radio artificial radioactivity / Give some examples of artificial radioactivity involving : alpha particles.

What is radio artificial radioactivity / Give some examples of artificial radioactivity involving : neutrons

Which of the noble gases is radioactive ?

Name two isotopes of hydrogen . Which of them is radioactive ?

Name the isotopes of hydrogen . Which of them is radioactive ?

Distinguish between Natural radioactivity and artificial radioactivity.