The answer is A: Core --> Mantle --> Crust.
Core: The earth's core is the center of the earth, which would ultimately be the deepest. The core is made up of alloy, which is a mixture of many medals, such as iron and nickel.
Mantle: The earth's mantle is the layer between the earths crust and core. Often made of silicate rocks.
Crust: The earth's crust is the outer-most of the three options. Usually made of up different types of rocks.
I think d because they are both increasing
The sound waves will get smaller and smaller till there is no more bc it is off.
Answer:
Diana's speed relative to ground is <u>16 km/h</u> in the direction of motion of train.
Explanation:
Given:
Velocity of train in forward direction is, 
Here, 
Velocity of Diana relative to train in the backward direction is, 
Negative sign implies backward motion or motion opposite to the direction of train's motion. Here, Diana is walking from front of train to back. So, Diana is moving in the opposite direction.
Now, we know that, for two bodies 'A' and 'B', velocity of 'A' relative to ground is given as:

Therefore, velocity of Diana relative to ground is given as:



So, Diana's speed relative to ground is 16 km/h in the direction of motion of train.