The answer is the second 1
So by looking at the seismic waves from earthquakes the scientist learned about the crust and the mantle but they also learned about the outer and inner core. To do this you have to look at a different kind of waves, the S (secondary waves) waves that also get released by an earthquake.
Im pretty sure its
A. Number of Organisms
B. Amount of Matter
A million sorrys if im wrong :(
The troposphere is shallowest or narrowest at the poles, and deepest or thickest at the equator. At the geographic North and South Poles, the troposphere reaches only 4 miles high, while at the equator, it extends nearly 12 miles high.