巷道施工开拓新水平的井巷第一次接近未揭露的煤层时,按照地测部门提供的掘进工作面距煤层的准确位置,必须在距煤层()以外开始打钻。
A.5m
B.8m
C.10m
D.15m
参考答案:C
阅读短文,判断正( T)误 ( F)。
A Shopping Trip
One morning Mr and Mrs Green go shopping in their car. In the shop they sec a lot of clothes.
Mrs Green likes them. So she buys a shirt for their son, a skirt for their daughter, and a sweater
for Mr Green. She buys a blouse for herself, too.
At about twelve o'clock, they go home, but they lose their way. Mr Green drives over to an old
man and asks, "Where am I?" " You're in your car, sir. " he answers.
( )1. Mr and Mrs Green go shopping in the afternoon.
( )2. Mrs Green buys a sweater for herself.
( )3. At eleven o'clock, they lose their way.
( )4. The old man is humorous (幽默的) .
下列心电图表现提示心房颤动的是()。
A.P波被f波取代,房率350~600次/分
B.P波被f波取代,房率250~350次/分
C.P波高尖,电压超过0.25mV
D.P波增宽,时间超过0.12s
E.P-R间期延长,时间超过0.12s