1. Put the layers of Earth in order from densest to least dense.
A. Crust, Mantle, Inner core, Outer Core
B. The inner core, Mantle, Outer core, Crust
C. Crust, Mantle, Outer core, Inner Core
D. The inner core, Outer core, Mantle, Crust
2. Which layer plays the greatest role in the movement of tectonic plates?
A. Crust
B. Mantle
C. Outer core
D. Inner core

1-A

2-B

Explanation:

2- mantle is liquid and moves crust

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.