What r punnet squares?

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Which best describes how the common cold spreads in the human body? a bacteria burst out of normal cells killing them b viruses replicate inside respiratory cells c bacteria inject dna into normal cells d viruses insert dna into bacteria

The kind of fertilization found in the majority of aquatic animals is (internal or external) fertilization.

Which of the following types of rock would most likely contain a fossil? slate granite lava rock limestone