Researchers tested the effects of acid rain on seedlings of two different species, camphor tree (cinnamomum camphora) and chinaberry tree (melia azederach). results of the experiments are shown here. note that acid rain caused a significant reduction of growth in chinaberry trees ( ∗∗∗ means p< 0.001), but not in camphor trees. what was the approximate percentage of growth reduction observed in the chinaberry trees treated with acid rain?