节能电动车为上海世博园区的游客提供了绿色交通服务。若一辆1.2t的电动车在世博大

题型:计算题

问题:

节能电动车为上海世博园区的游客提供了绿色交通服务。若一辆1.2t的电动车在世博大道上沿直线行驶,电动机的牵引力为300N。电动车行驶时的st图象如图所示。

求:(1)电动车受到的重力是多大(g取10N/kg)?

(2) 电动车以在0-25s内的行驶速度,行驶800m需要多长时间?

(3)在0-25s内电动车受到的摩擦阻力是多大?

考点:力的合成与应用
题型:计算题

闭经的治疗原则是()

A.除湿,调理冲任

B.养血,调理冲任

C.虚则补而通之,实则泻而通之

D.活血,调理冲任

E.益肝肾,调理冲任

题型:计算题

急性阑尾炎的体征有()

A.McBunley点压痛

B.McBunley点反跳痛

C.脐周压痛

D.上腹压痛

E.罗氏征阳性

题型:计算题

右图电路中,ab是完全相同的灯泡,线圈L的电阻可忽略.下列说法正确的是

A.合上开关Sb灯比a灯先亮,最后一样亮

B.合上开关Sb灯和a灯始终一样亮

C.断开开关S,a、b灯均过一会儿才熄灭

D.断开开关S,通过a灯的电流方向发生改变

题型:计算题

阅读理解。

     It's interesting that technology often works as a servant for us, yet frequently we become a servant to

it. Email is a useful tool but many feel controlled by this new tool. The average business person is getting

about 80 emails per day and many feel that about 80%of the messages in their in box are of little or no value.

     So, I have four suggestions to help you to become better at “Erasing Email”

     1.get off the lists. The best way to deal with a problem is to never have it. If you are receiving a lot of

unwanted emails, ask to be removed from the various lists. This would include your inclusion in unwanted

lists.

     2. “unlisted address”. Just as you keep an unlisted telephone number that you share only with those

whom you want to have direct access to , you might want to get a separate email address only for the

important communications you wish to receive.

     3.check it once or twice per day. Many I speak with are becoming chained to their email server,

monitoring incoming email continuously. Maybe this is because email creates its own sense of urgency, but

most of the communications are not all that urgent. I respond to them a couple of times per day.

     4. deal with it. As you open each email, do one of the following:

     a. if it requires a quick response, respond to it and delete it.

     b. if it requires a response but is not the best use of your time, try to find someone else to do it.

     c. if it is going to take any serious amount of time to respond, schedule it for action in your day planner

and then download the message, save it, or print it out for future action.

     I personally receive about 250 emails per day and by practising the suggestions above, I can handle that

volume in about an hour, taking advantage of this fantastic tool but not being controlled by it to make sure

I'm doing more important tasks in my day.

1. if you get unwanted emails, the best you can do is to _____.

A. make a list of them

B. put them into unwanted lists

C. send them to a special address

D. ask to be deleted from different lists

2. For the important communications, the writer suggests that you ______.

A. have a direct access for them

B. have several email servers for them

C. get a separate email address for them

D. get an unlisted phone number for them

3. To avoid being chained by the coming emails, what you can do is to ______.

A. respond urgent ones only

B. reply to all of them at the same time

C. handle them a couple of times daily

D. keep replying to emails all day long

4. To deal with an email you get, you can do the following except ______.

A. responding right away if it's urgent

B. downloading every email before you reply

C. scheduling it for later reply if it takes much time

D. asking someone else to reply to it if it's not at your convenience

题型:计算题

患者,女性,40岁。误服敌敌畏100ml,出现呼吸困难、瞳孔缩小、视物模糊、肌肉颤动。考虑其发病机制是

A.乙酰胆碱失效
B.肾上腺素过多
C.胆碱酯酶失活
D.甲状腺素过多
E.脑细胞水肿

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