A.5B.6C.7D.8
A.先降后升,炉膛负压先升后降B.先升后降,炉膛负压先降后升C.先升后降,炉膛负压先升后降D.先降后升,炉膛负压先降后升
A.0.8~1.4sB.0.5~0.8sC.1~2sD.0.3~1s