How long is an investigator required to keep consent documents, irb correspondence, and research records?

What are three uses of the yangtze river by the people living among the river

Agroup of anthropologists from the future want to study the culture and society of the twenty-first century. they cannot find any written documentation of this time period, so they must conduct an archaeological excavation. identify the artifacts, features, and ecofacts they will find during their fieldwork. what will these items tell the anthropologists about our culture and society?

What are the basic input of iron and steel industry