Casey paid $55.00 for 20 gallons of gas Friend Jackson Faith Xavier Gallons Amount Spent $33.60 $30.25 15 $39.00 $39.20 IMAM Dominic Which of her friends paid the same amount per gallon of gas? Jackson B Faith Xavier Dominic

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.