Answer:
Gills
Explanation:
Sharks are fishes and thus have gills through which they absorb oxygen from the water.
On the other hand, Whales being mammals use lungs to breathe. They can’t directly obtain oxygen from water.
The three main systems of government used today are unitary systems, federal systems, and confederate systems
The answer is C. It's kind of like how humans speak in different languages. So do birds. They may make different noises but they are all still birds.
The answer is the third one, mitochondrial DNA can be traced for generations. this is because geneticists could trace back mitochondrial adam and mitochondrial eve.
