A.
The planet contains matter and energy so it is a system.
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Answer:
1 and 2
Explanation:
It is given that, force exerted by air is negligible in any way.
Also, it is given that channel is in the shape of a segment of a circle with its center at O.
When it is within the frictionless channel at position 'Q',
A gravity exerts force on the ball in the downward direction. On the other hand, the channel pointing from Q to O also exerts a force on the ball.
However, there is no any force in the direction of motion. On the other hand, he channel pointing from O to Q does not exert a force on the ball.
Grass is a producer. It gets its energy from the sun, which i might add is by a process called,"photosynthesis", meaning the grass makes its own food. With this bew energy an animal such as a rabbit comes to eat it, that energy that the grass collected is now the rabbits.