Consider the experimental situation described below. Ability to grow in shade may help pines in the dry forests of Arizona resis
t drought. How well do these pines grow in shade? Investigators planted pine seedlings in a greenhouse in either full light or light reduced to 5% of normal by shade cloth. At the end of the study, they dried the young trees and weighed them. Identify the experimental unit(s) or subject(s). (Select all that apply.)
An experimental unit refers to the subject or factor under investigation. The subject or factor is subjected to different treatments in the course of the study. In the case of the experimental situation described above, the pine tree seedlings are the experimental units that actually received the treatments.
The treatments included being subjected to full or reduced light in the greenhouse. The response of the seedlings to these treatments would determine the outcome of the study.
