which geographic features protected the roman empire from barbarian invasions until the 4th century A. D

European nations have experienced many different forms of government. What kind of government did Francisco Franco create in Spain?

How are coastal dunes and coastal plains similar?

Which of these outcomes is a negative impact of agrarian societies on the environment? A. They provide a larger food supply for the population. B. They reduce biodiversity through the use of monoculture. C.

Which of the following substances is present in the Earth's atmosphere? water vapor, dust, ozone, plastic

What is the difference between erosion and deposition?

How high does the earth's atmosphere extend? A. 100 m B. 1,000 m C. 10 km D. 100km

How to grow plants in space?

Based on this map of oil imports, which nation imported the greatest number of oil barrels each day in the years before 2006? A. China B. Australia C. Canada D. the United States

How far will a P-wave travel in 9 min 20 sec?

The land in Mexico City is sinking. What is the primary cause of this problem? A. deforestation caused by cutting down trees B. too much water being taken from underground aquifers C. too many offices and towers being built in the city D.