Because those layers have been in existence longer than the layer on top of it.
The answer for this question would be the term SURGING. Surging is the fast-moving glacier that can move up to 6 kilometers per year. I<span>t flows more quickly, sometimes moving 10 to 100 times faster than it normally does. This is one of the classification of a glacier aside from the normal type. Hope this answers your question.</span>
Make an equation for both.
Ford= 15t+200
Chevy=20t
Now you must set them equal and solve for time t. Giving you 40 seconds. Now plug that in to the chevy equation to get 800 meters.
