Question

what could be explained from the straight horizontal line observed at the beginning and end of the graph

Answer 1

HEY MATE HERE IS YOUR ANSWER
It represtents the data which is infinilty extended. As we know, there are infinite numbers in the world. Therefore, for representing it on a graph the horizontal and vertical lines plays a crucial role. It denotes the infinite increase in numbers as the lines move upwards and downwards continuously without any break. Thus, the lines are denoted as two arrows representing the infinite growth of the number line.

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