The mobility of an electron in a conductor expressed in terms of

In the following circuit the $$5$$ $$V$$ zener diode requires a minimum current of $$10$$ $$mA.$$ For obtaining a regulated output of $$5V,$$ the maximum permissible load current $$\left( {{{\rm I}_L}} \right)$$, is ______$$mA$$ and the minimum power rating of zener diode is ________ $$W$$.