A tri-variate discrete distribution described by the following pmf p(x, y, z):

(1 mark) Obtained the marginal pmf of Y and verify it is a legitimate pmf.

(1 mark) Suppose we observe Y=2 and Z=5, what is the conditional pmf of X?

X=1 X=2 X=3 Y=1 0.10 0.20 0.00 Z =5 Y=2 0.00 0.05 0.05 X=1 X=2 X=3 Y=1 0.00 0.30 0.10 Z = 6 Y=2 0.05 0.05 0.10