Question

sponge is solid but how it can be compressed?

Answer 1

Because air is filled in gaps of sponge.
And therefore when we compress it the air moves out and it is compressed
hope it helps

Answer 2

hi buddy
here's your answer looking for

listen , sponge is solid only and if you gonna compress it then, it will compress.
but , don't forget about the big air gaps between them.
Because of that , it get compressed and air move out from it .

so, that's why it get compressed.

hope you are satisfied with my answer
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