Which pair of points has a negative slope? a) (-3, 17), (2, -8) b) (-3, 13), (3, 17) c) (4, 26), (-2, -10) d) (4, 14), (-2, -4)

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.