19时______分时,分针落后于时针100度.
(210-100)÷(6-0.5),
=220÷11,
=20(分);
即19时20分时,分针落后于时针100度.
故答案为:20.
The Changjiang River has been polluted badly and is not good _______.
A.to swim it
B.to be swum in
C.to swim in it
D.to swim in
当制冷剂含油浓度小于()时,不影响蒸发的沸腾传热系数。
A.6%
B.10%
C.15%
D.8%