Bones are made up of Calcium Phosphate given by the chemical formula, 
. When bones are kept in Hydrochloric acid, given by the chemical formula, HCl, they become soft because the calcium compound present in the bones changes its form. The following double displacement reaction takes place when the bones are kept in HCl,
---> 
Calcium chloride is water soluble, and gets washed away. This makes the bone thin and soft.
One action humans can take that might ensure that these sea otters will continue their function as
a keystone species in their environment is to (2) pass laws to regulate the hunting of sea otters.
Answer: "reflexes" .
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Explanation:
Mainly in ecology all the living and non living things are include so water must be in ecology as it is non living thing
