Dolphins
Dolphins are sea-mammals.
They have to breathe air or they will die. They are members of the Delphinidae family. Dolphins have smooth skin. Only baby dolphins are born with a few bristly hairs on their snouts. The hairs soon fall out. They have a long tail and the fin on the top of their backs keeps the dolphin from rolling over. The female dolphins have a thick layer of fat under their skin to keep them warm when they dive very deep. The dolphin’s front fins are called flippers. They use them to turn left and right. Dolphins grow from 2 to 3 meters long and weigh up to 75 kilograms.
Dolphins hunt together in a group. A group of dolphins is called a pod. They eat fish, shrimps and small squid. They live in salt water oceans. Dolphins can hold their breath for six minutes.
When dolphins hear or see a ship close by they go near it and follow it from many kilometers. Dolphins can leap out of the water and do some somersaults. Sometimes they invent their own tricks and stunts after watching other dolphins perform.
Dolphins are very friendly to people and have never harmed anyone. They are very playful animals.
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Which of the followings is not correct fact of dolphins?
a. Dolphins live in salt water oceans.
b. Dolphins have to breathe air because they are mammals.
c. Dolphins can hold their breath for six hours.
d. Dolphins eat other small sea livings.