Alskfkfjdkososkdbfbfifjfbskdnfbfbbdnskkdjrnf
Answer:
Na + CaSO4 = Na2SO4 + Ca
Explanation:
single displacement (substitution)
In Alpha decay two neutrons and protons are lost, so the mass decreases by four and the atomic number decreases by two.
Therefore the correct answer is B: Ra-224.