2. What are three factors that affect birth and/or death rates?

Political, economic, and religious

Explanation:

Age: Mortality rates are different in different age group. Mortality is high among children and old people but it is low among youths.

Sex/gender: Studies have shown that women have longer life expectancy than men. It may be due to biological and social causes that affectthe life expectancy. Besides, it is also found that death rate among infants is also similar to the life expectancy of adults. The death rates for male infants are higher than those of female infants.

Nutrition Levels: The children, especially under five years of age, die due to lack of nutritious foods. A balanced diet is a must for a healthy living. There are deficiency diseases caused by protein, energy, carbohydrate, malnutrition and also by micro-nutrient deficiencies. These are the causes of high death rates.

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.