Explain in complete sentences how a convection current is created.

A group of organisms of a certain species that is in one area at a given time is known as A an ecosystem B a community C a population D a trophic level

Name three types of organisms that are made of animal cells

Which of the following is not a result of heavy use of irrigation water? A. Leaching of nutrients B. Increase in salt concentration of the soil C. Increase in soil fertility D. Water shortages in western states

A visitor from space thinks a car is alive. Is he correct?

What trait is common to euglena and man? -multicellular material -ability to move -similar body color -one-celled material

If I turn my computer off at least once a week, it will run faster. What is the independent variable? What is the dependent variable? What are some controlled variables?

Which process is a "build up" process

Volcanoes, lightning, and the combustion of fossil fuels ALL contribute to acid precipitation. true false

Does an electric current cause a coiled wire to become an electric bell

Which is a renewable resource? A) coal B) sunshine C) gasoline D) natural gas