Uttar Pradesh has the highest population density in the Gangetic Plain, with over 800 people per square kilometer.

Jharkhand has the lowest population density in the Gangetic Plain, with less than 300 people per square kilometer.

The average population density of the Gangetic Plain is around 600 people per square kilometer.

Kolkata is the most populous city in the Gangetic Plain, with a population of over 4.5 million people.

Varanasi is the least populous city in the Gangetic Plain, with a population of less than 1 million people.

The high population density in the Gangetic Plain is due to a combination of factors, including fertile soil, favorable climate, and abundant water resources.

The main economic activities in the Gangetic Plain include agriculture, industry, and services.

The main challenges facing the Gangetic Plain include overpopulation, pollution, and climate change.

The government has implemented a number of policies aimed at addressing the challenges facing the Gangetic Plain, including family planning programs, pollution control measures, and climate change adaptation and mitigation strategies.

Individuals can help address the challenges facing the Gangetic Plain by reducing their carbon footprint, conserving water, and recycling and composting.