How many languages are spoken in Africa? * 10 points
less than 25
between 25 and 100
between 100 and 1,000
more than 1,000

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 answer ! find the alps. what countries and country borders intersect this major mountain range? which borders seem to be defined by the edges of the mountains? which borders seem to be defined by the edges of the mountains? which borders cut across the mountains?

What can happen to solar radiation when it enters earth’s atmosphere? check all that apply. it is absorbed by earth. it is reflected by clouds. it is reflected by glacial ice. it is condensed into visible light. it is amplified by water molecules.