为了保证除灰管道有一定的使用期限,在选择除灰管道的材料和确定管壁厚度时,都要充分地考虑()因素。
A.耐磨;
B.壁厚;
C.材料;
D.尺寸。
参考答案:A
.-Hi,Bruce.Here’s a letter for you.
-Thanks.I wonder_________.
A.who that letter was from
B.who was from that letter
C.who was that letter from
D.who from that letter was
痰湿咳嗽的特点是
A.痰黄咯吐不爽
B.痰中带血
C.痰黏腻稠厚成块
D.痰少粘连成丝
E.痰稀薄成水样