21. There must be enough sample to test properly.22. Asteroid impact may be a better term than meteorite collision.The impact made the atmosphere opaquer by filling it with dust, and indirectly, smoke, from fires touched off by hot impact debris. Since the atmosphere admitted much less sunlight, photosynthesis and plant productivity were curtailed, with disastrous results, especially for those with the greatest energy requirements, the dinosaurs. Of course, many dinosaurs were killed directly by the impact in areas nearest the Yucatan zero e.g. North America
Hepa filters can efficiently remove microbes from the air (Option a is correct).
<h3>What are Hepa filters?</h3>
Hepa filters, i.e., high-efficiency particulate air filters, are used to separate microorganisms from the air.
These filters (Hepa filters) eliminate over 99% of microorganisms such as bacteria, dust and pollen particles having a size higher than 0.3µm.
In conclusion, Hepa filters can efficiently remove microbes from the air (Option a is correct).
Learn more about Hepa filters here:
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I believe the biosphere is fragile, because over time all of the pollution us humans have made; If its from air pulloution, acid rain or even water pollution. the toxic acids over time have made the biosphere and the ozon layer weaker and more thin. which causes the biosphere to become weaker.
