can you help me answer these math questions!

Pls brainliest will be awarded if answer is correct

The vertices of a triangle are a(7.5), b(4,2), and c19. 2). what is

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.