The variable is the group that was given caffine, because thats what the doctors manipulated. They possibly altered the natural memory of the participants by giving them caffine. A more specific variable could be how much caffine each participant is given and what time are they given it.
Answer:
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<em><u>stream-of-consciousness</u></em></h2><h2 />
D. James Joyce's Ulysses is one of the most influential novels of the twentieth century, due largely to the innovations of the literary technique known as stream-of-consciousness.
Many North African nations practice Islam because many Muslims traded in that region, so the North Africans converted to Islam, whereas those in Sub-Saharan African nations were more prone to Christianity because of the trade they did with Europeans.
The great apes: orangutans, gorillas, chimpanzees, and humans
