A tugboat is pulling a barge into a harbor. The barge is exerting a force of 3000 N against the tugboat. Which force would most likely allow the tugboat to move the barge into the harbor?

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area

One of the purposes of transcription is to produce a sequence of bases that

Cells destroy body cells infected by a virus or bacteria. killer t t memory t none of the above