The natural rate of extinction as assumed by science is about 5 species per year. Currently scientists estimate we are losing species at 1000-10000 times that rate, with multiple species disappearing every day. A note on this idea is that the average extinction rate gives an unrealistic depiction of nature when we consider the catastrophic extinction events that ended the dinosaurs and shaped the ice age.
Earth's crust is made of rock, and rock is made of natural substances called minerals. There are three main types of rock: sedimentary, igneous, and metamorphic rock. Each type is produced in different ways. The oldest rocks on Earth were formed about 3.8 billion years ago.
Manipulated Variable:The speed working on maths problems
Responding Variable: The group that use¬ using a calculator
Controlled Variable:The same maths quetions
No. The answer is C, 1/4.
Answer:
It's the last one
Explanation:
The grand canyon was formed by erosion of water. That is the only option with erosion of water for the grand canyon
