Explain the questions comprehensively. Please provide a detailed and clear explanation for each situations.

1. A student asked, "Since electrical potential is always proportional to potential energy, why bother with the concept of potential at all?" How would you respond? 2. It is easy to produce a potential difference of several thousand volts between your body and the floor by scuffing your shoes across a nylon carpet. When you touch a metal doorknob, you get a mild shock. Yet contact with a power line of comparable voltage would probably be fatal. Why is there a difference? 3. In electronics it is customary to define the potential of ground (thinking of the earth as a large conductor) as zero. Is this consistent with the fact that the earth has a net electric charge that is not zero