简述性别认同障碍的诊断标准。

求2.4的7倍，列式为______．

—Are these books ____?

—No, they are not his. They belong to ____.

A．Tom, her

B．Tom’s, her

C．Tom, hers

D．Tom’s, hers

道床阻力是由轨枕和道床相互作用产生的，道床纵向阻力阻止轨枕纵向位移，影响长钢的轨伸缩。

阴虚火旺型郁证的治法是（）

A.滋阴

B.清热

C.养心

D.镇心

E.安神

The disadvantage of using three strand nylon line for towing is its（）.

A.inherent weakness

B.tendency to rot if left damp

C.danger to crew if it parts

D.strength and shock absorbing abilities