Which of the following countries is not part of central america?

a) el salvador

b) argentina

c) costa rica

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.

Look at the diagram showing the different wavelengths in sunlight. which statement describes electromagnetic waves with wavelengths greater than 700 nanometers? they take the form of heat. they can cause skin cancer and sunburn. they are some of the shortest waves. they can be seen by human eyes as visible light.

The days of the “midnight sun,” when the sun never really sets at night, occur during what season?