A Pediatrician Is Interested in Determining If Cognitive Development Scores

Short Answer

A pediatrician is interested in determining if cognitive development scores are lower for low-birthweight infants than normal infants. She has 49 active cases involving low-birthweight infants from who she could collect data to compare to the national average. What would power be assuming the following effect sizes and α = .05?
a.
=.20
b.
=.50
c.
=.80