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(08.01 MC) A political action group that wants to overturn the Montreal Protocol monitors the ozone layer via satellite across the South Pole for the months of May and June. They find that the layer has the same thickness as the historical average. They claim that ozone depletion was not affected by the protocol. What is the major flaw in their reasoning?

(07.02 MC) Which of the following, if it occurs near a wetland, could lead to eutrophication?Runoff from crop fields that have been treated with large doses of fertilizerOil runoff from roadsLeeched metals from a mine

(08.02 LC) Which of the following is a greenhouse gas but does not contribute significantly to global climate change?

(08.04 LC) A forest has just been clear-cut to make room for a subdivision and has increased carbon in the atmosphere. What is the impact of deforestation on oceans?

(08.05 MC) Some people think that boaters should be required to thoroughly clean their boat hulls before bringing the boats into waterways on public lands. What is the most likely reason for this?

(07.05 MC) This graph compares the dose-response curves for a lethal dose of a particular toxin and a dose that results in liver damage: According to the graph, approximately how much larger is the LD50 dose for this toxin than the ED50 dose resulting in liver damage?

(07.01 MC) Tamika had added young koi fish to her waterfall pond and had them for over a year until they all suddenly started dying. She talked with a neighbor, who also had koi fish that died a few years ago at a relatively young age. Which of the following could be a possible reason for why the fish died?

(07.01 MC) Which of the following best shows the results of biomagnification from years of rainfall washing mercury (Hg) into bodies of water such as lakes, rivers, and streams?

(08.05 MC) Many national parks that allow camping prohibit people from carrying in firewood from other areas. What is the most likely reason for this?

(07.05 LC) This graph shows the dose-response curve for a lethal dose of a particular toxin: According to the graph, approximately how much larger is the LD50 dose for this toxin than the threshold level?