Nyquist plot consider a feed back system where the OLTF is: $$G(s) = {1 \over {s\left( {2s + 1} \right)\left( {s + 1} \right)}}.$$ Determine the asymptote which the nyquist plot approaches as $$\omega \to 0.$$ Find also the range of 'k' in terms of the cross over frequency $${\omega _{PC}}$$ for stability.

Indicate which of the following logic gates can be used to realize all possible combinational Logic functions:

Among the digital IC-families-ECL, TTL and CMOS:

A logic family has threshold voltage $${V_T}$$= 2V, minimum guaranteed output high voltage $${V_{OH}}$$= 4V, minimum accepted input high voltage $${V_{IH}}$$ = 3V, maximum guaranteed output low voltage $${V_{OL}}$$ = 1V, and maximum accepted input low voltage N $${V_{IL}}$$ =1.5V. Its noise margin is