๋น„ํŠธ ํ”Œ2% ์ฐ์–ด๋„ ๋ช‡๋ช‡์•ŒํŠธ๋“ค๋นผ๋ฉด ์ฃ„๋‹ค ํ”Œ0.5~1% ์‚ฌ์ด