Both of the nations are members of the g-20 major economies, organisation for economic co-operation and development and the united nations.
Extraneous
An <em>extraneous variable</em> is a variable in an experiment that you are not intentionally studying. These variables usually provide undesired affects on the experiment.
In this example, the independent variable is whether a sentence is humorous or not, and the dependent variable is the memory performance score. However, because the humorous sentences are only given to males, and the non-humorous sentences are only given to females, gender becomes an extraneous variable as you are not intentionally testing gender's relation to the dependent variable, but it is still affecting the experiment.
Synthetic materials, heavy metal, pollutants