Question: Unfortunately, the layer of good ozone is being destroyed by air pollution. The chief culprits are chlorine and bromine gases. They are released in aerosol sprays, coolants, and other products. Loss of ozone has created an ozone hole over Antarctica. Ozone depletion results in higher levels of UV radiation reaching Earth. In humans, this increases skin cancers and eye cataracts. It also disturbs the nitrogen cycle, kills plankton, and disrupts ocean food webs. The total loss of the ozone layer would be devastating to most life. Its rate of loss has slowed with restrictions on pollutants, but it is still at risk. Two neighboring habitable planets from the same solar system, planet U and planet N, had Earth-like atmospheres. The inhabitants of planet U destroyed the ozone layer by their actions, while their neighboring planet N didn't. Which planet had inhabitants that used fewer aerosol coolants?
Answer: planet N

Question: Mass is a measure of the amount of matter in a substance or an object. The basic SI unit for mass is the kilogram (kg), but smaller masses may be measured in grams (g). To measure mass, you would use a balance. In the lab, mass may be measured with a triple beam balance or an electronic balance, but the old-fashioned balance pictured below may give you a better idea of what mass is. If both sides of this balance were at the same level, it would mean that the fruit in the left pan has the same mass as the iron object in the right pan. In that case, the fruit would have a mass of 1 kg, the same as the iron. As you can see, however, the fruit is at a higher level than the iron. This means that the fruit has less mass than the iron, that is, the fruit's mass is less than 1 kg. Johnathan is trying to find two blocks of wood with the same mass for a project he is working on. He doesn't have a balance, so he makes a crude one out of materials he has on hand. He put a block of wood on either side and the block on the left side was at a lower level than the block on the right. Does the block of wood on the left side have more or less mass than the block of wood on the right side?
Answer: more

Question: Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in the lithosphere. The motivating force for seafloor spreading ridges is tectonic plate pull rather than magma pressure, although there is typically significant magma activity at spreading ridges. At a spreading center, basaltic magma rises up the fractures and cools on the ocean floor to form new seabed. Hydrothermal vents are common at spreading centers. Older rocks will be found farther away from the spreading zone while younger rocks will be found nearer to the spreading zone. Additionally spreading rates determine if the ridge is fast, intermediate, or slow. As a general rule, fast ridges have spreading (opening) rates of more than 9 cm/year. Intermediate ridges have a spreading rate of 59 cm/year while slow spreading ridges have a rate less than 5 cm/year. Two geology students had an exam on plate tectonics. Bobby learned more about divergent tectonic plates, while Nate was more confident in explaining everything about Convergent plates. Which student knew more about fractures occurring in the lithosphere?
Answer:
Bobby