Why do we know so little about the indus valley civilization? what evidence do we have that the indus valley people were an advanced civilization?

The first answer is- The reason why the Indus Valley Civilization vanished is still unknown. Not many artifacts have been found to let us gain insight into their culture. Their writing was also mostly in Sanskrit, which no one can translate in this day and age.    

The 2 answer is Best  Their great architectures and their systems also most of the houses had toilets in them which was uncommon at the time

name two ways organisms join a population and two ways organisms leave a population. two ways organisms join a population are birth rate and immigration. two ways they leave are death rate and emigration.

explanation:

silk

indigo  

rice

all the other answers are wrong