A doctor gives a patient a (D)rug (drug" or no drug"), dependent on their (A)ge (old" or young") and (G)ender (male" or female"). Whether the patient (R)ecovers or not (recovers" or does not recover") depends on all three variables D, A, G. Further, it is given that (A G | ).

1. Write down the belief network for the above scenario.

2. Mathematically derive the computation of p(recovers | drug).