Design a 7.5V zener regulator circuit using a 7.5V zener specified at 12mA. The zener has an incremental resistance of r and a knee current of 0.5mA. The regulator operates from a 10V supply and has a 1.2k-ohm load. What is the value of R you have chosen? What is the regulator output voltage when the supply is 10% high? Is 10% low? What is the output voltage when both the supply is 10% high and the load is removed? What is the smallest possible load resistor that can be used while the zener operates at a current no lower than the knee current while the suplly is 10% low? What is the load voltage in this case?