Researchers wanted to evaluate whether a certain herb improved memory in elderly adults as measured by objective tests. To do this, they recruited 99 men and 130 women older than 70 years and in good health. Participants were randomly assigned to receive the herb, 30 mg 3 times a day, or a matching placebo. A measure of memory improvement was determined by a standardized test of learning and memory.

for finding the midpoint of any given 2 pair of points simply add the respective x coordinates with other x coordinate and the y coordinate with other y coordinate and divide them by 2

in your question it will be :

(3+1)/2 for the x coordinate of mid point i.e 2

[8+(-4)]/2 for the y coordinate of midpoint i.e 2

so coordinates of mid point of points (3,8) and (1,-4) will be (2,2)

it is x=-4

step-by-step explanation:

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step-by-step explanation:

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