Read and circle the correct word. As a planetary geologist, Bethany Ehlmann studies our solar system. She
wonders / leads to how the rocks on Mars were formed and how they interacted
with water. She also is looking for degrees / proof that life could have been or could be
present on the Red Planet. She works closely with Curiosity, a six-wheeled robot called
a rover. Rovers can move around and explore. Curiosity travels through the plains
and valleys / aspects on the surface of Mars. It uses scientific
dust / instruments to analyze the Martian proof / landscape.
Bethany hopes that Curiosity's work, combined with new
technological advances, will one day provide the answer to the
fundamental / satellite question: Is there life beyond Earth?

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.        

the money supply is the total amount of money available in the economy. how do changes in the money supply affect people and businesses?

this statement is true.

forests are public goods, available for everybody. when usage of such a good becomes interesting for consumers and its usage increases, there can be a risk of overexploitation. it is a non rival good therefore, if one person consumes the good it does not reduce the availability for subsequent consumers.

these caracteristics require the establishment of measures in order to prevent the destruction of a commonly owned space, for example, to restrict the amount of people that have access to the same time.

it would be d). more resources must be obtained to attain that combination of goods and services