20世纪初，科学家先后提出了如图①、②、③所示的三种原子模型，依照提出时间的先后顺序正确的排列是（   ）

    The booking notes of the play “The Age of Innocence”:

    Price: $10

    DISCOUNTS;

    Saver: $2 off any seat booked any time in advance for performances from Monday to Thursday. Savers are available for children under 16, over 60s and full-time students.

    Supersaver: Half-price seats are available for people with disabilities and one companion. It is advisable to book in advance. There is a maximum of eight wheelchair spaces available and one wheelchair space will be held until an hour before the show.

    Standby: Best available seats are on sale for $6 from one hour before the performance for people eligible (suitable) for Saver and Supersaver discounts and thirty minutes before for all other customers.

    Group Bookings: There is a ten percent discount for parties of twelve or more.

    School: School parties of ten or more can book $6 standby tickets in advance and will get every tenth ticket free.

    Please note: We are unable to exchange tickets or refund (退款) money unless a performance is cancel led due to unforeseen circumstances.

BOOKING:

    There are four easy ways to book seats for performance:

    In person: The Box Office is open Monday to Saturday, 10a. m.- 8pm.

    By telephone: Ring 01324976 to reserve your tickets or to pay by credit card (Visa, MasterCard and Amex accepted).

    By post: Simply complete the booking form and return it to Global Theatre Box Office.

    On line: Complete the on-line booking form at www. Satan fiedtheatre. com.

已知$\underset{n\to \infty }{\lim }$a_n=3，$\underset{n\to \infty }{\lim }$b_n=$\frac{1}{3}$，则$\underset{n\to \infty }{\lim }$$\frac{a_n-3b_n}{2a_n}$=____

阅读理解

    I had arrived at the airport to catch an early flight home.It had been a very busy three days for me on an interstate trip with lots of meetings，business to do and new customers to meet.Then came the announcement that the flight had been delayed due to a technical problem.I could see a group of technicians and ground staff rushing about，obviously trying hard to fix the problem.I watched and listened as many of the passengers sitting near me shared their frustration about the inconvenience.

    As I sat waiting，I reflected on my last meeting for the day.It was not a business meeting but rather a very enjoyable and brief lunch with an old business associate and friend I had not seen for over 12 years，and who I had worked with for nearly 15 years before we lost in touch.I had been given his phone number by a customer I had visited on the first day of my trip，so I called him out of the blue and made a time for us to meet.

    Our lunch was spent recollecting(回忆) times gone by and as well filling each other in on what had happened in our lives over the last 12 years.Our conversation was frequently interrupted with statements such as 'remember when we did...'，'whatever happened to...' and of course the one we all liked to hear...'you know you haven't changed one bit，except for a few more grey hairs.'

    We both laughed and smiled as we recalled the good times and the great experiences we had shared over the 15 years we had worked together. Each event we discussed caused another recollection and everything we talked about centered on the good times.Almost at the same time，right at the end of our time together，we both said how much we both enjoyed it and that we must do it again.We agreed to catch up when I was next in town，then said our goodbyes and I was off to the airport.

    So with this extra time on my hands as I waited for my flight，it was great to revisit and replay in my mind all that we had talked about over lunch.I realized at that moment just how important it is to have regular reminders of the good times in your life and to be able to take the time to recall the past，for so much of what we have done in our past，shapes us and makes us who and what we are today and beyond.

    At the end of my busy trip with the focus on getting all the business done，I was indeed fortunate enough to have had the chance to take a short break and reflect on the good things that had happened in my life over 12 years ago.It was somewhat like looking at an old photo album that you have found stored away in a cupboard in your house.There before your eyes are lots of wonderful memories in print that take you back to that time and place，and most importantly to those people who are in the photos.It also made me realize that when you get caught up doing what has to be done in the moment，it is easy to forget the people you have met in your life who have made a positive effect on and enriched you，often in only the smallest of ways.

    My flight home was finally called nearly three hours later and yes as you would have expected many of the passengers cheered when the announcement was made.I smiled as I boarded the plane and realized that I was not at all upset about the delay，as I had been able to spend much of my time reflecting on the good times from days gone by and now eagerly look forward to many more opportunities to recall the past.