c) Given is a set of rules for detecting symptom of chickenpox. Apply forward chaining inference and backward chaining towards the given set of rules as below.

General Rules:

U1: IF patient has red rash

AND viral infection

THEN patient has chickenpox

U2: IF patient temperature > 37.5

THEN patient has fever

U3: IF patient felt sick more than three days

AND patient has fever

THEN suspect a viral infection

Fact:

D1: Patient temperature is 39

D2: Patient has been sick for 4 days

D3: Patient has red rash

i) Use the forward chaining inference for finding the conclusion.

ii) Use the backward chaining inference for proving the goal Patient has chickenpox.