In the recent financial crisis we have seen what has been commonly been named as "bank runs" like for example in Northern Rock (something similar has been seen in supermarkets related to toilet paper in the recent Covid-19 crisis). Can you explain, in the lights of models we have seen in class, why this phenomenon can occur? Is there any measure related to deposits that can prevent such banks runs? Can you think of other circumstances in which similar phenomena can occur? Be brief, concise and use the concepts and models we have learned in class. (20 points)