We associate certain environments with peacefulness and productivity, such as parks, gardens, and forests. Psychologists want to investigate if the presence of indoor green plants can improve concentration levels in a university library. They plan to use an experimental design, comparing the concentration levels of students working in a study room featuring several large green plants with students in an identical study room containing no plants at all.
Suggest one open question you could use to obtain some additional qualitative information in this study.
