用附合导线方法测量一级海控点时,附合导线边长总长不得超过()公里
A.10
B.20
C.30
D.50
参考答案:C
损伤性血气胸呼吸困难的主要原因是()。
A.气体交换量减少
B.回心血量减少
C.心脏排血阻力增加
Most species of this plant thrive in ordinary well-drained garden soil and they are best planted 8 cm deep and 5 cm apart.
A.develop well
B.grow taller
C.mature
D.bear fruit