Radioactivity help

Hi,

I have attached a question on radioactivity.
How are you supposed to know if in the question there is more radiation or if there is just one?
Also, why does alpha and beta radiation deflect in different directions (and why in those directions)?

Thanks!

alpha and beta particles carry electrical charges - moving charged particles are deflected in magnetic fields.
the direction in which they're deflected depends on whether they're positively charged or negatively charged.
look up the charge carried by alpha and beta particles.

Why does it depend on the charge?
Alpha is positive, beta is negative and does gamma have no charge? Is that why it is not deflected?

Thanks!