Take the breakdown voltage of the zener diode used in the given circuit as $6\, V$. For the input voltage shown in figure below, the time variation of the output voltage is : (Graphs drawn are schematic and not to scale)

The value of power dissipated across the zener diode $\left( V _{ z }=15 V \right)$ connected in the circuit as shown in the figure is $x \times 10^{-1}$ watt. 

The value of $x ,$ to the nearest integer, is …………..

In connection with the circuit drawn below, the value of current flowing through $2\, k \Omega$ resistor is …………. $\times 10^{-4} A$

The reading of ammeter in the following circuit will be….$mA$

A zener diode having breakdown voltage equal to $5\,V$ is used in voltage regulator circuit shown in figure, the current through diode is……..$mA$