# How to find the most likely decays in 2 hadrons for $\Omega$?

I took a look at the Particle Data Group, and the most likely modes are $$\Omega ^{-}\rightarrow \Lambda K^{-}$$ (68%) and $$\Omega ^{-}\rightarrow\Xi ^{0}\pi ^{-}$$ (24%). I have 2 questions:

1) The exercise only says that it can decay in 2 hadrons, but it doesn't say which ones. How can i know this without looking at books as i did?

2) Once i find the particle couples, how can i calculate the transition probability? Solution is given by Fermi's Golden Rule $$\Gamma _{if}=2\pi |<\Psi _{i}|H_{Int}|\Psi _{f}>|^{2} \rho(E_{f})$$ , but how can i calculate the density $$\rho(E_{f})$$ and the matrix element?