A designer needing a well-regulated 15 V supply in an application where a poorly-regulated 24 V source is available, considers the use of a shunt regulator string consisting of a series string of two 6.8 V Zeners and two junction diodes. Available Zener diodes are specified to have Vz = 6.8V at 20 mA with rz = 5 D. Available junction diodes are 10-mA types modelled at 10 mA by a 0.7 V drop and a 2.5 series resistance. Design a suitable regulator for desired operation with a 15 mA nominal load. What does the output of your design become if the supply is 10% high, the series resistor is 5% low, and the load is accidentally removed? What is the power dissipated in each 6.8 V Zener under the worst combi-nation of these conditions?