Scientist: Cross-sections of stalactites - calcite formations deposited on cave ceilings by seeping water - can reveal annual va
riations 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.
Would weaken the hypothesis beacuse it would show that many droughts indicated in the stalactites do not always show a collapse in society. Societes could therefore cope with droughts.
It is known that the luminosity of a star is proportional to its effective temperature to the 4th power. This means that the ratio between the brightness of stars A and B is equal to the ratio between their temperatures to the 4th power:
Bangladesh is a country that is flood prone and has ground water contamination.
Explanation:
The ground water contamination is serious threats to the water reserves of bangladesh and is a major public problem. The arsenic contamination wa first identified in the north district of bangladesh since 1993.
Some recommendations for prevention and conservation of groundwater in Bangladesh.
Providing safe and hygienic drinking water options
Involving local government
Providing proper management of patient thright proper follow up methods.
Regular monitoring of arsenic
Encouraging research on groundwater contamination and issuing recommendations of toxicity and management.
The focus is the place inside Earth's crust where an earthquake originates. The point on the Earth's surface directly above the focus is the epicenter. When energy is released at the focus, seismic waves travel outward from that point in all directions.
