24. In our experiment, we filled 4 tubes with water and bromothymol blue.
Tube 1 did not contain an organisms, tube 2 contained a snail, tube 3
contained a elodea and tube 4 contained both a snail and elodea. What
tubes could photosynthesis occur in?
O Tubes 3 and 4
O Tubes 2 and 4
O Tubes 2, 3, and 4