d. The farther away the bees 5. Many plants and trees, with

Last updated: 7/9/2022

d. The farther away the bees 5. Many plants and trees, with the help of a nitrogen-fixing bacteria, take nitrogen from the air and convert it into a usable form. A student wants to find out if the redbud tree helps to put nitrogen into the soil. She designs an experiment in which she measures the amount of nitrogen in the soil around redbud trees and pine trees, before and after nitrogen-fixing bacteria are added to the soil. What is a logical hypothesis for the student's experiment? a. Redbud trees grow faster when soil nitrogen is present. b. Nitrogen-fixing bacteria populations grow faster when soil nitrogen is present. Redbud trees increase soil nitrogen levels with the help of nitrogen-fixing bacteria. C. d. Nitrogen-fixing bacteria increase soil nitrogen levels.