Q: Electronic ear protectors work differently. They identify high-amplitude sound waves and send sound waves through them in the opposite direction. This causes destructive interference with the waves, which reduces their amplitude to zero or nearly zero. This changes even the loudest sounds to just a soft hiss. Sounds that people need to hear, such as the voices of co-workers, are not interfered with in this way and may be amplified instead so they can be heard more clearly. This type of hearing protector is recommended for higher noise levels and situations where it's important to be able to hear lower-decibel sounds. Carson is a construction worker that operates a jack hammer on the construction site for a new building. The jack hammer is often incredibly loud and generates a high amount of noise. Carson wants to protect himself from this noise, but he also needs to be able to hear the orders given to him by his boss on the site. Would electronic ear protectors reduce or increase the amplitude of the jackhammer?
A: reduce

Q: 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. Russian research spent most of their time in Antarctica to study the loss of ozone in the atmosphere. The Canadian team went north of the Polar Circle, close to the North Pole to do the same thing. They spent several months there. The Canadian team didn't find any ozone holes at the North Pole. Which team didn't observe the disruption of the nitrogen cycle?
A: Canadian

Q: All living organisms must have the ability to reproduce. Living things make more organisms like themselves. Whether the organism is a rabbit, or a tree, or a bacterium, life will create more life. If a species cannot create the next generation, the species will go extinct. Reproduction is the process of making the next generation and may be a sexual or an asexual process. Sexual reproduction involves two parents and the fusion of gametes , haploid sex cells from each parent. Sexual reproduction produces offspring that are genetically unique and increases genetic variation within a species. Asexual reproduction involves only one parent. It occurs without a fusion of gametes and produces offspring that are all genetically identical to the parent. two groups of students studied animal reproduction. Group Alpha studied sexual reproduction, while group Beta studies asexual reproduction. Which group of students learned more about increased genetic variation within a species?
A: Alpha

Q: As shown here, pressure decreases to less than 25% of ground-level atmospheric pressure when we get to an altitude of about six miles. Since this is a common cruising altitude for commercial airplanes, pressurized cabins are needed for the comfort and survival of the passengers. This is because the density of the air decreases along with the decreasing air pressure, so there is less oxygen in a breath of air. You've probably noticed this effect in high-mountain areas, as it often feels harder to breath. Mark and Jordan want to take a trip together. Mark wants to go mountain climbing while Jordan wants to go to a concert out of state. Jordan sometimes has a hard time breathing as well so they take this into consideration while making the plans for their trip. Will there be more oxygen in the air at the top of the mountain or at the concert?
A:
concert