A.電子天平 B.蒸發(fā)皿 C.坩堝 D.燒杯
A.13mm B.15mm C.13cm D.15cm
A.手擰,手感到有阻力時再繼續(xù)擰半圈 B.手擰,手感到有阻力立即停止 C.扳手擰,手感到有阻力立即停止 D.板手擰,手感到有阻力時再擰半圈