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If a and b are the measures of two first quadrant angles and sin a = 4/9 and sin b = 2/5 find sin(a+b).

Acertain standardized? test's math scores have a? bell-shaped distribution with a mean of 520 and a standard deviation of 105. complete parts? (a) through? (c)

Determine if the function below is continuous. a. continuous b. not continuous, 1 hole c. not continuous, > 2 holes d. not continuous, 2 holes