Arsenic can be extracted from its ores by frst reacting the ore with oxygen (called roasting) to form solid As4O6, which is then reduced using carbon:

Predict the direction of the shift of the equilibrium position in response to each of the following changes in conditions.
a. Addition of carbon monoxide
b. Addition or removal of carbon or tetraarsenic hexoxide (As4O6)
c. Removal of gaseous arsenic (As4)