Given below in the the left column are different modes of communication using the kinds of waves given the right column.

A	Optical Fibre communication	P	Ultrasound
B	Radar	Q	Infrared Light
C	Sonar	R	Microwaves
D	Mobile Phones	S	Radio Waves

An n-p-n transistor operates as a common emitter amplifier, with a power gain of 60 dB. The input circuit resistance is 100$$\Omega $$ and the output load resistance is 10 k$$\Omega $$. The common emitter current gain $$\beta $$ is :

n moles of an ideal gas with constant volume heat capcity C_V undergo an isobaric expansion by certain volume. The ratio of the work done in the process, to the heat supplied is :

A moving coil galvanometer allows a full scale current of 10^–4 A. A series resistance of 2 M$$\Omega $$ is required to convert the above galvanometer into a voltmeter of range 0-5 V. Therefore the value of shunt resistance required to convert the above galvanometer into an ammeter of range 0.10 mA is :