<span>Experiments</span>
An experimental research entails a
controlled test of a cause-and-effect relationship that researchers suspect
exists. Experiments involve a researcher directly controlling or manipulating
changes in the independent variable by exposing participants to the treatment
conditions. It is undertaken to make a discovery or test a hypothesis
The more Carbon Dioxide in the air, the more it increases the GREENHOUSE EFFECT.
Yes the us president should be elected by national popular vote
They do this to evaluate the nations economy and GDP or gross domestic product