Instructions for Q4 (Model ) of holiadys hw

Q. Trace the history of origin of different pulses from the world.
Depict in the form of model.
Instructions:
For this question students can depict the history in the following ways
1. In the form of flow chart./ timeline chart
2. On the world map trace the history of origin of pulses.
3. it can be one pulse or pulses. As per your choice.