The relationship of two species that can be represented as +/0 would best be described as

when a reversible reaction is occurring in both directions at the same rate; the products and reactants do not change in concentration. a chemical reaction where the compound is broken into its constituent parts.

the answer is d. embryo

the correct answer is: " ventricles " .

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hello, ballerbaby1265. i would say that the child has had a concussion due to the fall and their symptoms. 60 beats per minute is normal in a child that is sleeping, but not while awake. two of the main symptoms of a concussion after are both sleepiness and being tired. i hope i have a great night.