With $10$ V dc connected at port A in the linear nonreciprocal two-port network shown below, the following were observed:

1. $1 \: \Omega$ connected at port B draws a current of $3$ A
2. $2.5 \: \Omega$ connected at port B draws a current of $2$ A

For the same network, with $6$ V dc connected at port A, $1 \: \Omega$ connected at port B draws $7/3$ A. If $8$ V dc is connected to port A, the open circuit voltage at port B is

1. $6$ V
2. $7$ V
3. $8$ V
4. $9$ V
in new
recategorized