PLEASE ANSWER! I’LL GIVE BRAINLIS! 1. A bird flaps it’s wings downwards to fly. How does this Keep the bird up in the air?
2. A fish pushes the water with its tail fin. What will happen to the first and why

Explanation:

1 .A bird flies by use of its wings. The wings of a bird push air downwards. In turn, the air reacts by pushing the bird upwards. The size of the force on the air equals the size of the force on the bird; the direction of the force on the air (downwards) is opposite the direction of the force on the bird (upwards).

2.Fish swim by flexing their bodies and tail back and forth. Fish stretch or expand their muscles on one side of their body, while relaxing the muscles on the other side. This motion moves them forward through the water. Fish use their back fin, called the caudal fin, to help push them through the water.

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