Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group (no relaxation training) or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. the independent variable in this study is

its d. you give me brainliest

president reagan was a good presidant and should be presidant if he was still alive

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a factory opens that mass-produces light bulbs.

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not sure if that's an answer to your questions but this is an example! : )

swahili is an extremely rich and complex civilization, a set of ethnic groups articulated by a language and a series of cultural elements that fuse the african traditions, islam and indian culture. this growth was largely a result of the indian ocean trading network that brought in not just man-made riches, but also religious ideas, specifically islam, which had a significant impact on the local culture. furthermore, the development of the swahili language gave a common cultural unity to the people.