管制的接受单位需要在管辖空域外接受移交，应当（）。A.尽早与航空器进行联络 B.得到

已知f（x）=|x|+|x-1|，若g（x）=f（x）-a的零点个数不为0，则a的最小值为______．

作为基因的运输工具—载体，必须具备的条件之一及理由是　　　[ ]

A．能够在宿主细胞中稳定地保存下来并大量复制，以便提供大量的目的基因

B．具有多个限制酶切点，以便于目的基因的表达

C．具有某些标记基因，以使目的基因能够与其结合

D．它的参与才能够使目的基因在宿主细胞中复制并稳定保存

高档珠茶的外形特征一般为：（），墨绿起霜。

善意占有属于( )行为。

A．合法占有

B．非法占有

C．合法

D．所有人占有

In the workplace, influenza is typically spread by infected individuals to others with whom they work in close quarters. A new medication that suppresses the symptoms of influenza therefore will actually increase the number of influenza cases, because this medication will allow people who would otherwise be home in bed to return to work while infected.
Which of the following, if true, most seriously challenges the prediction

A．Coughing, a symptom of influenza that the new medication suppresses, is a primary mechanism in the spread of this illness.

B．Some medications that are used to suppress symptoms of influenza are also used by many people to treat symptoms that are caused not by influenza but by other illnesses.

C．Many workers who now remain at home when infected with influenza do so because the symptoms of influenza prevent them from performing their jobs effectively.

D．Most adults who are immunized against influenza in order to avoid being infected are over 65 years old and retired and thus do not work outside the home.

E．(E) Symptoms of an illness are often the body’s means of curing itself of the illness, and therefore suppression of symptoms can prolong the illness that causes them.