Select an equation that is equivalent to a^2-144b^2 a) (a-12b)^2 B) (a+12b)^2 C) (a-12b)(a+12b) C) a^2-24ab+144b^2

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.