Find the average of 37 & 72

Write a function for a rotation 90 degrees counter clockwise about the origin, point 0

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.

Which of the following statements would be sufficient to prove that parallelograms pqrs is a rectangle ?