1. a pair of potentiometers
2. a pair of synchros
3. a differential transformer
4. a metadyne
5. a control transformer

1. TWT
2. Low pass/High pass filter
3. Low power 20 dB attenuator
4. 40 dB directional coupler with matched load
5. Power meter.

Assertion (A): To add 8 bit words, two 1C 74181 can be cascaded.

Reason (R): In 1C 74181 a sum greater than 15 leads to high carry out.

Assertion (A): Hollow waveguides are frequently used as transmission lines at microwave frequencies.

Reason (R): Waveguide has high power handling capacity, low loss and simple structure.

Assertion (A): In a circuit having high inductance, reactive power may be more than apparent power.

Reason (R): Reactive power = VI sin θ.