The one most familiar to me is 4. For some reason my fedilab app on GrapheneOS won't render 1. People who have never seen a 3.5" floppy seem to manage the famous save icon, so maybe it's what we know in an interface that counts most.
U+1D70 LATIN SMALL LETTER N WITH MIDDLE TILDE: ᵰ – Unicode
ᵰ, codepoint U+1D70 LATIN SMALL LETTER N WITH MIDDLE TILDE in Unicode, is located in the block “Phonetic Extensions”. It belongs to the Latin script and is a Lowercase Letter.
U+1F1F7 REGIONAL INDICATOR SYMBOL LETTER R: 🇷 – Unicode
🇷, codepoint U+1F1F7 REGIONAL INDICATOR SYMBOL LETTER R in Unicode, is located in the block “Enclosed Alphanumeric Supplement”. It belongs to the Common script and is a Other Symbol.
滱, codepoint U+6EF1 CJK UNIFIED IDEOGRAPH-6EF1 in Unicode, is located in the block “CJK Unified Ideographs”. It belongs to the Han script and is a Other Letter.
, codepoint U+13F14 EGYPTIAN HIEROGLYPH-13F14 in Unicode, is located in the block “Egyptian Hieroglyphs Extended-A”. It belongs to the Egyptian Hieroglyphs script and is a Other Letter.