For the synchronous sequential circuit shown below, the output $$Z$$ is zero for the initial conditions $${Q_A}{Q_B}{Q_C} = Q{'_A}Q{'_B}Q{'_C} = 100.$$

The minimum number if clock cycles after which the output $$Z$$ would again become zero is _____________.

For a $$3$$ -input logic circuit shown below, the output $$Z$$ can be expressed as

The mean square value of the given periodic waveform f(t) is_________.

For the network given in figure below, the Thevenin's voltage V_ab is