[There is a big water container for the experiment. We can see an orange floating on the water.]
The air pockets make "a)the orange" lighter than the water, so it floats.
How , then, can you sink "b)the orange"?
...It sinks because "c)the orange" is now denser than the water.
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Thank you for your help. One more questions as follows.
a), b), c) Are they used as a specific orange? Or in generic use?
All are referring to one particular orange in that container of water, yes.
a), b), c) are used as generic terms to refer to "the orange" in different scenarios or conditions.
In the first sentence, "a) the orange" refers to the orange when it is floating on the water. The sentence explains that the air pockets in the orange make it lighter than the water, causing it to float.
In the second sentence, "b) the orange" refers to the same orange, but now the question is asking how to sink it. The sentence explains that by changing the density of the orange, it can be made denser than the water, causing it to sink.
In the third sentence, "c) the orange" again refers to the same orange, but now it explains the reason why the orange sinks. The sentence states that the orange sinks because it has become denser than the water.
So, a), b), and c) are used as placeholders to indicate different situations or conditions of the orange, rather than representing specific oranges.