The helium isotope 6/2 he is unstable. what kind of decay would you expect it to undergo? what would the resulting nuclide be?

The isotope is likely to undergo beta decay. This is because it is too small to release alpha particles. The beta decay will result in the number of neutrons decreasing and the number of protons increasing. After decay of one beta particle, the resulting nuclide will be:
6/3 which is Lithium

The type of Decay that i would expect to undergo is The Beta Decay, a type of a radioactive decay which will Emmitt electron
After it undergoes its process, the atom that is left after the Decay is  6 3 Li

hope this helps