Consider a system represented by the block diagram shown below. Which of the following signal flow graphs represent(s) this system? Choose the correct option(s).

 




Step 1: Understand the block diagram. The system consists of two blocks \( G_1 \) and \( G_2 \), where the feedback path comes from the output \( Y(s) \) that goes to \( G_1 \), and the output from both \( G_1 \) and \( G_2 \) contribute to \( Y(s) \). 
Step 2: Identify the corresponding signal flow graph. The system has a feedback loop, where the output \( Y(s) \) feeds back into \( G_1 \). This is correctly represented by option (B), where \( G_1 \) has feedback from the output \( Y(s) \). Thus, the correct answer is (B).
A positive-edge-triggered sequential circuit is shown below. There are no timing violations in the circuit. Input \( P_0 \) is set to logic ‘0’ and \( P_1 \) is set to logic ‘1’ at all times. The timing diagram of the inputs \( SEL \) and \( S \) are also shown below. The sequence of output \( Y \) from time \( T_0 \) to \( T_3 \) is _________.

Consider a part of an electrical network as shown below. Some node voltages, and the current flowing through the \( 3\,\Omega \) resistor are as indicated. 
The voltage (in Volts) at node \( X \) is _________. 

 
The 12 musical notes are given as \( C, C^\#, D, D^\#, E, F, F^\#, G, G^\#, A, A^\#, B \). Frequency of each note is \( \sqrt[12]{2} \) times the frequency of the previous note. If the frequency of the note C is 130.8 Hz, then the ratio of frequencies of notes F# and C is: