5. Consider the belief network of Figure 8.35, which extends the electrical domain to include an overhead projector.

Answer the following questions about how knowledge of the values of some variables would affect the probability of another variable.

(a) Can knowledge of the value of Projector_plugged_in affect your belief in the value of Sam_reading_book? Explain.

(b) Can knowledge of Screen_lit_up affect your belief in Sam_reading_book? Explain.

(c) Can knowledge of Projector_plugged_in affect your belief in Sam_reading_book given that you have observed a value for Screen_lit_up? Explain.

(d) Which variables could have their probabilities changed if just Lamp_works was observed?

(e) Which variables could have their probabilities changed if just Power_in_projector was observed?