(A) plutonium
(B) U-235
(C) thorium
(D) radium
Answer: (A) plutonium
Plutonium is a man-made element. It is a radioactive chemical element.
(A) plutonium
(B) U-235
(C) thorium
(D) radium
Answer: (A) plutonium
Plutonium is a man-made element. It is a radioactive chemical element.