What causes two distinct pressure zones between the equator and the poles? A. Earth's rotation
B. The troposphere interacting with the mesophere
C. The ozone layer
D. The fact that nitrogen is heavier than oxygen

What is the amount of organic matter in all living organisms in a habitat called?

Acivilization exists for several hundred yeaars, developing its own language. such a civilization probably has been: a. farming corn b. suffering from a lack of contact with the outside world. c. isolated by mountains or some other physical barriers. d. starving from lack of trade.

To solve this system of equations by elimination, what operation could be used to eliminate the y-variable and find the value of x? 6x + 5y = 2 4x + 2y = 8 a) subtract 2 times the second equation from 3 times the first equation b) subtract 3 times the second equation from 2 times the first equation c) subtract 5 times the second equation from 2 times the first equation d) subtract 2 times the second equation from 5 times the first equation