Which ocean current is responsible for the cold, dry air? What type of current is it?

Needed fast 15 points the process of natural selection favors certain characteristics in organisms, while it selects against other characteristics. what would happen if there was zero variation between all of the organisms on earth? a.organisms would evolve to increase variety b.natural selection would operate faster c.less food would be available d.evolution through natural selection would not occur

Scientist: cross-sections of stalactites—calcite formations deposited on cave ceilings by seeping water—can reveal annual variations in rainfall in particular areas over hundreds and thousands of years. we often found that when—according to these cross-sections—drought occurred in a particular area, it coincided with the collapse of an ancient society in that area. i hypothesize that drought reduced agricultural productivity in these areas, thereby leaving these societies without the resources needed to handle internal stresses and external threats. which of the following, if true, would most weaken the support for the scientist's hypothesis? a. many droughts indicated in the cross-sections of stalactites do not correspond with the collapse of a society in that area. b. information from the cross-sections of stalactites alone cannot reveal the level of agricultural output in an area at a particular time. c. most of the societies that collapsed during droughts did so when internal power struggles coincided with military raids from neighboring societies. d. most of the societies that collapsed during droughts maintained large stockpiles of food and water at the time of their collapse. e. information from stalactites also suggests that the collapse of some societies coincided with periods of abnormally high rainfall.

Plz hury on a timer which statements explain what happens at deep-ocean trenches? check all that apply. crust is formed. mountains are formed. seafloor spreading occurs. crust becomes molten rock. denser plates slide under lighter plates.