离场航空器在爬升过程中，保持本场的（）直至到达过渡高度。
参考答案：QNH
Nick is looking for another job because he feels that nothing he does____ his boss.
A．serves
B．. satisfies
C．promises
D．supports
视黄醛是由下列哪种物质转变而来（）。
A.维生素B
B.维生素K
C.维生素A
D.维生素B12
E.维生素C
