19. Name four points. 20. Name two line segments.
21. Name three rays.
22. Name two angles.
23. Name the line three ways.

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.