An urn contain 5 balls, white and green. The experiment consists in grab 2 balls from the urn and register the pair , where we observe a white ball and otherwise. What is the bayes estimator for considering the squared loss function? (i.e )

I can't figure out which posterior distribution I should use or even if I need to use one. I calculated my loss function considering all the possible values for and $ but I can't calculate the risk function without the posterior function.

Can someone help me with it?

I can't find out what to do with the ordered pair, I just calculated the probability of each pair