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If 90° < θ < 180° and cotθ = -1/3, then cscθ =

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

Scores on the cognitive scale of the bayley-scales of infant and toddler development range from 1 to 19, with a standard deviation of 3. calculate the margin of error in estimating the true mean cognitive scale score, with 99% confidence, if there are 12 infants and toddlers in a sample.