66、关于散弹以下说法正确的是( )。

　直放图像弹头呈黑色圆形

　直放图像弹头外部有绿色圆环

　斜放图像呈圆柱状,弹头呈黑色

　斜放图像底部圆心是底火部分

正确答案：ABCD

68、X射线机材料分辨力用英文表示为( )。

32、X射线机穿透力用英文表示为( )。

17、Your baggage is 10 kilos( ), I’m afraid you have to pay for excess baggage.

16、Passengers to San Francisco by Flight CA 783, please go through( ).

15、——What will happen to me if I refuse the security check?
——( ).

14、Sorry sir,you have to( ) this baggage,for it is too large and will cause you a lot of inconvenience.

13、Passengers,if you haven’t got a boarding card and a baggage check,please go to the( ) to go through the check-in procedures first.

12、A: Are you going to take a domestic or an international flight?

68、A: What’s the( ) of the delay?

31、X射线机灰度分辨力用英文表示为( )。