Exercise 5.7 Consider the following knowledge base and assumables aimed to explain why people are acting suspiciously:

goto forest ← walking.

get gun ← hunting.

goto forest ← hunting.

get gun ← robbing.

goto bank ← robbing.

goto bank ← banking.

fill withdrawal form ← banking.

false ← banking ∧ robbing.

false ← wearing good shoes ∧ goto forest.

assumable walking, hunting, robbing, banking.

(a) Suppose get gun is observed. What are all of the minimal explanations for this observation?

(b) Suppose get gun ∧ goto bank is observed. What are all of the minimal explanations for this observation?

(c) Is there something that could be observed to remove one of these as a minimal explanation? What must be added to be able to explain this?

(d) What are the minimal explanations of goto bank?

(e) What are the minimal explanations of goto bank ∧ get gun ∧ fill withdrawal form?