1) Suppose that a doctor wants to use a placebo for a patient

1) Suppose that a doctor wants to use a placebo for a patient. The doctor decides to inject distilled water into one of the patient's veins. Decide whether or not this would be a wise decision and justify your decision 

2) All enzymes have an optimal temperature at which they work as well as an optimal pH for their activity. Does this mean that enzymes only work at those specific temperatures and pH optimums? Briefly explain your answer using evidence from the unit that supports your answer.