<span>b. becomes weaker
try this </span>
Reversals are the rule, not the exception. Earth has settled in the last 20 million years into a pattern of a pole<span> reversal about every 200,000 to 300,000 years, although it has been more than twice that </span>long<span> since the last reversal.</span>
Answer:
1. Least massive stars are the coolest and least luminous, lower right of main sequence, on HR diagram.
2. Most massive are the hottest and most luminous, upper left of main sequence on Hr Diagram.
3. The radius of stars are related to their sprectral type. having the O being the hottest upper left and M being the coolest bottom right.
Answer:


Δd = 
Explanation:
As
, when the car is making full stop,
.
. Therefore,

Apply the same formula above, with
and
, and the car is starting from 0 speed, we have

As
. After
, the car would have traveled a distance of

Hence 
As
we can simplify 
After t time, the train would have traveled a distance of 
Therefore, Δd would be 
Answer:
D. the wind picking up dust and carrying it
Explanation:
Erosion is a process in which an agent transfer the top soil to another region, thereby exposing the lower soil. These agents have the ability to move the top layer of soil and deposit it at another place. The major agents in this case are; a running or flowing body of water and wind.
Therefore, the change to the Earth's surface that is an example of erosion is the wind picking up dust and carrying it. Thereby exposing the lower layers.