Tropical forests contain dense trees, which allow less sunlight to penetrate. emergent trees are trees that grow to a height of more than 45 to 55 meters, above the usual height of trees in tropical forests. which system provides the best possible explanation for why these trees grow to those heights?
a.
growth pattern
b.
homeostasis
c.
nervous system coordination in plants
d.
phototropism

Of the pollutants that form acids in the atmosphere, which is easiest to reduce? a. sulfur dioxide b. nitrogen dioxide c. ozone d. carbon monoxide

Group control group #1 experimental group yes yes yes control group #2 no new drug orange juice bed rest no yes no yes ves which of the following is the best explanation of why a second control group was included in this experiment? o a. to provide the volunteers in the study with something to drink o b. to prove that the common cold cannot be cured c. to confuse anyone who is trying to steal their new drug and sell it as their own invention o d. to researchers conclude that results are related to the new drug and not to the orange juice submit e previous

Rarefaction is used for which of the following? a. creating a representative sample b. studying how disease impacts populations c. rediscovering species thought to be instinct d. determining which sea creatures live in an area