Question

in the process of _____, earths surface is worn down by wind, glaciers, and water.
○ a folding
○ b desertification
○ c erosion
○ d plate movement

question 19 (2 points)
the ______model uses birthrates and death rates to show changes in the population of a countr
○ a population explosion
○ b population growth rate
○ c migration
○ d disease rate

Explanation:

First Question (about Earth's surface process)

• Option a: Folding is a tectonic process involving rock layers bending, not surface wearing by wind/water/glaciers.
• Option b: Desertification is land turning to desert, not surface erosion.
• Option c: Erosion is defined as the process where Earth’s surface is worn down by agents like wind, glaciers, and water.
• Option d: Plate movement is about tectonic plates shifting, not surface wearing.

• Option a: "Population explosion" is a term for rapid growth, not a model using birth/death rates.
• Option b: The population growth rate model uses birth rates and death rates (along with migration, sometimes) to show population changes.
• Option c: Migration is a factor in population change, not a model using birth/death rates.
• Option d: Disease rate relates to illness prevalence, not population change via birth/death rates.

Answer:

c. erosion

Second Question (about population model)