（Ⅰ）求椭圆的方程；

（Ⅱ）设O为坐标原点，在椭圆短轴上有两点M，N满足 $\overrightarrow{OM}=\overrightarrow{NO}$ ，直线PM、PN分别交椭圆于A，B．

（i）求证：直线AB过定点，并求出定点的坐标；

（ii）求△OAB面积的最大值．

根据短文内容，从短文后的选项中选出适当的选项补全短文，并将选项的编号字母依次填入题号后横线上。

Have you ever taken photos by using mobile phones with selfie sticks(自拍杆)? ____ 

However, a pair of US artists from New Mexico, Arie Snee and Justin Crowe believe they have invented a better one and they call it “selfie arm”.

____ It makes those people in the pictures seem to be holding hands

with a loved one.

The pair say it offers a far better experience than using a straight stick. The selfie arm makes people feel they are not alone when they take photos.

____They think their invention solves the main problem that the selfie stick has — people look alone while they are taking pictures of themselves with great interests. The product, at present, just an art project and a model conveniently provides you a welcoming arm.____The pair say they are fascinated by these new ideas.

The “selfie arm” is made of fiberglass. ____ The project that they work on shows the growing selfie stick

Phenomenon (现象) directly and the increasing need for narcissism (自恋) and Internet agreement.

A．It is lightweight and  easy-taking. 

B．Thousands of “selfie arms” have been made.

C．It seems that they are together with their friends.

D．For better or worse, they have taken the world by storm.

E．This new invention is a small, useful and cleverly-designed tool.

F．And better yet in the future, it'll talk in a friendly way and never get angry or upset.

    Are you suffering from FOMO—that is, Fear Of Missing Out? Research shows that a growing number of young people are, with worrying reasons for their sleep and schoolwork.

    ____ You aren't able to do your best unless you sleep well. Most experts agree that the optimum（最适宜）number of hours is eight, and this has been accepted as common sense for as long as I can remember. However, I was young once and know most of you get much less sleep than that.

    I read an interesting article in a teachers' magazine recently. ____ Worryingly, the results showed that teenagers are facing a new problem. They may go to bed and get up at appropriate times, but a growing number are waking up in the middle of the night, not to use the bathroom or have a snack, but because of FOMO.

    According to the article, the number of students waking up during the night to check social media is growing. Afraid of missing a comment or opportunity to take part in a chat, teenagers are waking at all times of the night, going online and getting involved. ____

    Experts are worried about this growing trend and the report reveals some worrying statistics: 23% of 12-to 15-year-olds wake up nearly every night to use social media. ____ One in third of the students are constantly tired and unable to function to their full capacity.

    So I'd like to ask you to be responsible when it comes to social media. Switch off your devices at night. The world won't end and your social media will be waiting to greet you in the morning! ____

A. But things are getting out of hand.

B. They did a study of 848 students in Wales.

C. Another 15% wake up at night once a week for the same reason.

D. I give you my word that you won't have missed anything important.

E. All happens when they should be sound asleep.

F. FOMO is the fear that everyone else is having more fun and more excitement than you.

G. Everybody knows how important it is for students to get a good night's sleep every night