Fill in the blanks:
In the two bit full-adder/sub tractor unit shown in Fig., when the switch is in position $$2.$$ $$.....$$ using $$.....$$ arithmetic.

For the synchronous counter shown in fig. write the truth table of $${Q_0},\,\,{Q_1}$$ and $${Q_2}$$ after each pulse starting from $${Q_0} = {Q_1} = {Q_2} = 0$$ and determine the counting sequenced also the modulus of the counter

What is the modules of the counter with initial state $${Q_2}\,{Q_1}\,{Q_0} = 000$$

Show with the help of a block diagram represent Boolean function:
$$f=AB+BC+CA$$ can be realized using only $$4:1$$ multiplexer.

Find the minimum product of sums of the following expression
$$f = ABC + \overline A \,\overline B \,\overline C .$$