When using non-polite (not -impolite- speech, mind, just not です/ます form) speech, の is often used to replace ～んです or ～んですか at the end of a sentence. This implies the person is giving you (or asking you for) extra information.
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When using non-polite (not
When using non-polite (not -impolite- speech, mind, just not です/ます form) speech, の is often used to replace ～んです or ～んですか at the end of a sentence. This implies the person is giving you (or asking you for) extra information.