Hey there!
Airplanes must be pressurized when flying at high altitudes so that the oxygen levels stay normal for us to breathe. The higher you go up, the thinner the air gets, which causes breathing problems for us humans.
Thank you!
One piece of evidence to support the theory that south America and Africa were once connected; Continental Drift.
Answer:
transform plate boundary
Tectonic setting of the San Andreas Fault (transform plate boundary) in California, the subduction zone (convergent plate boundary: oceanic-continental collision) in the Pacific Northwest.
The answer is National security because the citizens need to know that they are being protected, and usually also how they are being protected. But the government often needs so measure of secrecy in order to protect National Security. If the government were to tell citizens exactly how they were being protected and someone posted it onto the internet it would severely compromise that protection. However people do not generally seem to understand that and tensions become heated between the two groups. Both sides reasons are perfectly legitimate, but one outweighs the other by knowledge. The answer is B.
