How are data presented using ploygraphs?

Explanation

Polygraph is a line graph in which two or more than two variables are shown by an equal number of lines for an immediate comparison, such as the growth rate of different crops like rice, pulses or the birth rates and life expectancy or sex ratio in different states or countries. A different line pattern such as straight line (______________) ,, broken line (---) dotted line (...) or a combination of dotted and broken line (....) or line of different colours may be used to indicated the value of different variables.