the world's current population is 7.3 billion and the world population in 1915 was 1.8 billion. The increase over the past century is 7.3 billion - 1.8 billion = 5.5 billion. So, the correct answer would be "more than 5 billion" (option D).
The answer is <span>b. water erosion
Water erosion moves water downhill and during this process, different landforms are formed. <u>Some of them are rills, gullies, streams, rivers, tributaries</u>, waterfalls, floodplains, meander, lakes, etc.</span>
Some general properties include the following
1.) Color
2.) Hardness
3.) Luster
4.) Streak
5.) Odor
Hope that helped!
I believe it’s D. It can be a cycle