This type of listening response is called back-channel signal. This allows the speaker to know that the listener is attentive or willing to engage a conversation between them. It is shown through short utterances, facial expressions, head nods and others.
A reversible change is a change that can be undone or reversed
A. The water
Biotic factors mean living this such as frogs, grasshoppers, snakes, etc.
Aboriginal factors means non-living such as water, temperature, sunlight, etc.
Abiotic factors are the non-living parts of the environment that have a major influence on living organisms which makes water an abiotic factor.
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