Answer:a
Explanation:
because there is special use for it
Answer:
the ocean
Explanation:
The salmon, for example, migrate downstream to the ocean, where they live until adulthood. When they are mature, the fish return to their birthplace to reproduce. When they return, they are captured and harvested.
Kidney preserve or excrete H⁺ ion and HCO₃⁻ ion to regulate the blood pH.
Answer:
B
Explanation:
because they belong to classe Echinoidea, phylum echonodermata
