Being radioactive and unstable elements they are continuously changed.
Radium and polonium doesn't changed the world.
The discovery (not invention) of polonium and radium didn't changed the history.
Radium and polonium are radioactive natural chemical elements.
Polonium and radium doesn't affect history.
Polonium and Radium .
Radium and polonium are principally alpha emitters.
Polonium and radium are radioactive elements and toxic; they are dangerous.
Yes, radium and polonium are radioactive elements.
The radium and polonium elements were and still are radioactive elements.
Both radium and polonium are radioactive elements and are not stable.
Polonium (Po) and radium (Ra) are two different chemical elements.
Polonium and radium are radioactive chemical elements but they have not the same properties.