The author contrasts two very successful high jumpers, Stefan Holm and Donald Thomas. What central or main idea is revealed by the contrast between these two jumpers and the very different ways they achieved their success? Sportsgene

Oceans produce approximately 80 percent of the oxygen our planet needs to support animal life. pollution that reaches the ocean through dumping, oil leaks, runoff, and other processes interferes with that oxygen production and poses a real threat to the oxygen content in our atmosphere. if the oxygen content decreases, it is likely that carbon dioxide will increase. this could have dramatic consequences for life as we know it. which does this passage indicate causes a decrease of oxygen in the atmosphere?