Which of the following is an example of chemical weathering

Jerry wants to consume no more than 45% of his calories from carbohydrates. calculate his requirement for calories from carbohydrates based on a 2,500 kcal per day intake.

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

Natural selection changes allele frequencies because some survive and reproduce more successfully than others.