从哪里输入导航数据库？A、位于左侧操纵台上的DBU B、位于右侧操纵台上的DBU C、位

患者男，35岁。因急性阑尾炎拟行手术治疗。患者同时患有急性间隙性血卟啉病。

血卟啉病的原发性缺陷是缺乏（）

A.维生素B₁₂

B.维生素A和维生素D

C.尿卟啉原合成酶

D.2，3-=磷酸甘油酶

E.卟吩胆色素原

A few years ago, when I was still in high school, I met a wonderful and warm teacher. At that time in my life, there were many changes to adjust to, apart from the usual teenage troubles. My parents had divorced, so my elder brother and I had chosen to stay with my dad. Due to the fact that he was keeping the house, we didn’t have to move.

During this time, my teacher took a special interest in me. Being my English teacher, she encouraged my mind to travel to creativity I had long given up. She brought me out of the shell I built.

She became my mother, my older sister, my friend and my teacher. The one thing she couldn’t do though was to make me more girly as growing up with only my dad and brother made me a real tomboy.

Sometimes, I would be really immature（不成熟的）, especially if she was scoring me less than others on purpose. She knew I could do better than what I was handing in and so pushed me to extend further than limits.

When I finished school and then after college I was about to leave my hometowns she gifted me a watch that every second, with my pulse, should remind me of the one person who will forever wait and love me without reservation.

Time has passed and our friendship is distant, but in my heart, soul and mind, she is the closest I ever got.

小题1:The writer and her elder brother chose to live with their father simply because _________.

A．their mother was expecting to have another baby

B．they didn’t have to move out of their house

C．they hated their mother remarried

D．they had a closer relationship with their father小题2:How did the writer get along with her studies before she met her English teacher?

A．She was hopeless and had given up her studies.

B．She was getting along well with her studies.

C．She had some trouble with her studies.

D．She lacked interest in creativity.小题3:The writer behaved herself like a boy because ________.

A．she needed the love of mother

B．she wanted to learn from her father and brother

C．she lived with only men all the time

D．her English teacher didn’t care about her小题4: What was the writer’s attitude to the watch given by the teacher?

A．She considered it to be very useful.

B．She valued it very much.

C．She kept it very well.

D．She wanted to do something later in return for it.

产品层次中，()是产品向消费者或用户提供的基本效用或利益。

A.核心产品

B.有形产品

C.形式产品

D.附加产品

关于能的概念，下列说法正确的是[ ]

A．用线悬挂着的物体，它没有做功，它不具有机械能

B．在空中飞行的子弹，因为它能做功，所以它具有机械能

C．甲物体的运动速度比乙物体的大，则甲物体的动能一定比乙物体的大

D．甲物体的高度比乙物体的高度大，则甲物体的势能一定比乙物体的大

商用车是指用于运送人员（9座以上的）和货物的汽车。