To examine the calming effect of pets during stressful situations, you recruited 60 five- year-old children who owned pets and had them perform a stressful task. You randomly assigned the children into three treatment groups and had them perform the task either alone (control group), with a parent, or with their pet present. Their average heart rate (in beats per minute) during the task was recorded and you calculated SStreatment = 298.3 and SSerror = 621.1. The results of their ANOVA were significant (p<0.05). Required:
a. Write the appropriate null and alternative hypotheses for this analysis.
b. List one potential confounding variable and explain the impact it might have on the results.