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

Blank is a naturally occurring gas that's found in most soils and rocks and can cause lung cancer

Data courtesy of the un development programme 2006-2008 and world bank 2009 the chart above compares measures of development using the hdi and gdp. why might turkey rank lower in the hdi indicator even though it has a high gdp?

What are some of the impacts of humans on the earth?