Answer:
The balanced chemical reaction is given as:

Explanation:
When aqueous cesium sulfate and aqueous barium perchlorate are mixed together it gives white precipitate barium sulfate and aqueous solution od cesium perchlorate.
The balanced chemical reaction is given as:

According to reaction, 1 mole of cesium sulfate reacts with 1 mole of barium perchlorate to give 1 mole of a white precipitate of barium sulfate and 2 moles of cesium perchlorate.
The correct answer is Gamma decay. It happens after beta and alpha decay
because what's left after those two can enter a new process of gamma
decay. This releases gamma rays which is a more complex term for the
photons that you mentioned before. These rays can be dangerous for
humans so care not to get caught in them.