A.10ppm B.20ppm C.100ppm D.30ppm
A.立即 B.聽監(jiān)督指揮 C.根據(jù)當(dāng)時(shí)實(shí)際情況決定是否 D.留下繼續(xù)工作
A.1.8ppm;預(yù)警 B.2.8ppm;預(yù)告 C.3.6ppm;警惕 D.4.6ppm;警示