John prepared stethoscope with a paper cup and plastic tube. Write down the procedure of preparation. (AS3)

a. Material required to make stethoscope are Paper cups and string.

b. To make stethoscope, Take paper cup which is in the shape of funnel and size of 6-7 cm.

c. Fix a rubber tube at narrow end of the paper cup.

d. Then fix the paper cup in shape with the help of an elastic string.

e. Put the pen end of the cup on your chest and the rubber tube in your ear and you can hear the heart beat