Answer is (1) - less mass and greater penetrating power.
Alpha particle is a ₂⁴He nucleus while beta particles are electrons. Hence, the mass of alpha particle is greater than the mass of beta particle. But, the penetrating power is higher in beta particle than alpha particle. Alpha particles can be blocked by few papers but beta particles can go through those papers.
I believe the answer is A. single-displacement
Answer:
https://prnt.sc/ql75rv
This is a link to an image of the lewis structure.
Its electronic confuguration is 2.8.6 so it occupies 3 shells.