In this study, what percentage of variance in serum antibody levels is explained by the consumption of milk proteins in children with autism?

You are asked to conduct a study to determine whether there is an association between consumption of milk proteins and levels of serum antibodies in children with autism. You randomly select 50 children previously enrolled in an autism clinical trial, and they are the sample for the study. You select an alpha of 0.05 and a power of 0.80.