Environmental Science for AP* (2nd Edition)

Published by W. H. Freeman
ISBN 10: 1464108684
ISBN 13: 978-1-46410-868-6

Cumulative - AP Environmental Science Practice Exam - Section 1: Multiple-Choice Questions - Page EXAM-1: 4

Answer

(a)

Work Step by Step

The experiment lacks a control treatment. because a control group (saplings grown at ambient gas levels only) is essential to compare the effects of elevated gases. The answer is (a).
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.

GradeSaver will pay $15 for your literature essays
GradeSaver will pay $25 for your college application essays
GradeSaver will pay $50 for your graduate school essays – Law, Business, or Medical
GradeSaver will pay $10 for your Community Note contributions