Answer:
A healthy ear is filled with air
Explanation:
Catalysts are substances that cause a chemical reaction to occur in a different way than it would otherwise happen without that catalyst – a catalyst could cause a reaction to happen at a faster rate, or at a lower temperature, than would be possible without the catalyst.<span>
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Answer:
7. C
Explanation:
The more above is the layer, the more recent it is. So the bird lived after 'cause it was in a layer above.
A useful index fossil must be distinctive or easily recognizable, abundant, and have a wide geographic distribution and a short range through time.
