Question 4 Suppose you are in charge of a toll bridge that is essentially cost free. The d

Consider following Figure. Assuming TCP Reno is the protocol experiencing the behavior shown above, answer the following questions. In all cases, you should provide a short discussion justifying your answer. 1). What is the value of ssthresh at the 24th transmission round？ 2). During what transmission round is the 70th segment sent？ 3). Assuming a packet loss is detected after the 26th round by the receipt of a triple duplicate ACK, what will be the values of the congestion window size and of ssthresh？ 4). Suppose TCP Tahoe is used (instead of TCP Reno), and assume that triple duplicate ACKs are received at the 16th round. What are the ssthresh and the congestion window size at the 19th round？ 5). Continue with question 10), and again suppose TCP Tahoe is used, and there is a timeout event at 22nd round. How many packets have been sent out from 17th round till 22nd round, inclusive？

see her until she comes back to college in the fall. Question: What time does the conversation probably take place？

A．At the beginning of the term.

B．Towards the end of the term.

C．During the Christmas season.

D．During the summer vacation.

Section B

Directions: This section is to test your ability to understand short conversations. There are 2 recorded conversations in it. After each conversation, there are some recorded questions. The conversations and the questions will be spoken only once. When you hear a question, you should choose the correct answer from the 4 choices marked A, B, C, and D.

听力原文：M: May I speak to Petty？

W: Speaking.

M: Good morning, Petty.

W: Good morning, Steward.

M: I'd like to discuss your suggestion with you as soon as possible. Would Tuesday be all right for you？

W: Tuesday. That's tomorrow？

M: Yes.

W: Let me see. How about tomorrow, say, 8:30？

M: Then suppose I come to your office at 8:30 tomorrow.

W: Good. I'll be expecting you then,

M: Thank you. Good-bye.

W: Good-bye.

(6)

A．8:30 in the morning, Tuesday.

B．8:30 in the evening, Tuesday.

C．8:30 in the morning, Monday.

D．8:30 in the evening, Monday.

Question 3

A medium-sized city has two major industries: financial services and manufacturing of electronic equipment. Suppose that restrictions on interstate competition in the market for financial services lead to a large expansion of the financial services sector in the city.

(a)What effect do you predict that this increase in jobs would have oil wages and housing prices in the city？

(b)What effect do you think there would be on the manufacturing sector in the city？ Would you expect that manufacturing employment would rise or fall？

Question 3

A medium-sized city has two major industries: financial services and manufacturing of electronic equipment. Suppose that restrictions on interstate competition in the market for financial services lead to a large expansion of the financial services sector in the city.

(a)What effect do you predict that this increase in jobs would have oil wages and housing prices in the city？

(b)What effect do you think there would be on the manufacturing sector in the city？ Would you expect that manufacturing employment would rise or fall？

Section B

Directions: This section is to test your ability to understand short conversations. There are 2 recorded conversations in it. After each conversation, there are some recorded questions. The conversations and the questions will be spoken only once. When you hear a question, you should choose the correct answer from the 4 choices marked A, B, C, and D.

听力原文：M: May I speak to Petty？

W: Speaking.

M: Good morning, Petty.

W: Good morning, Steward.

M: I'd like to discuss your suggestion with you as soon as possible. Would Tuesday be all right for you？

W: Tuesday. That's tomorrow？

M: Yes.

W: Let me see. How about tomorrow, say, 8:30？

M: Then suppose I come to your office at 8:30 tomorrow.

W: Good. I'll be expecting you then.

M: Thank you. Good-bye.

W: Good-bye.

Q6: What time do the two speakers agree to meet？

(6)

A．8:30 in the morning, Tuesday.

B．8:30 in the evening, Tuesday.

C．8:30 in the morning, Monday.

D．8:30 in the evening, Monday.

Question 2

The world producer price for baseballs is ＄24 per dozen, and almost all of them are produced outside the U.S. Suppose the U.S demand curve is QD=100,000-2,000P, where P is price per dozen, and Q is measured in dozens. The U. S domestic supply curve is QS=-10,000 + 1,000P.

(a) Before a tariff is imposed, what is the U. S equilibrium price？ Domestic consumption？ Domestic production？ Imports？

(b)Congress has decided to help the baseball manufacturing industry for national security reasons, and it imposes a tariff of ＄6 per dozen. What are the new equilibrium price, domestic consumption, domestic production, and imports？

Section B

Directions: This section is to test your ability to understand short conversations. There are 2 recorded conversations in it. After each conversation, there are some recorded questions. The conversations and the questions will be spoken only once. When you hear a question, you should choose the correct answer from the 4 choices marked A, B, C, and D.

听力原文：W: How will you like college, Simon？

M: I doubt if I'll like where it is and its size. It looks as if it's very small.

W: Yes, it's very pleasant. There are only about a thousand students.

M: What kind of students comes here？

W: That's a difficult question to answer. I suppose it's an impossible question to answer, really. There are all kinds. They're difficult to describe.

M: What do they do in their spare time？

W: All kinds of things. There are a lot of different kinds of clubs to join. Some students meet their friends at the Union. Some go to the library to study.

M: Do they have to go to the library to study？

W: No, they can study where they want to.

M: Do you know what sports they play？

W: Oh, yes, there are teams for all kinds of sports.

M: It sounds as if going to college is fun.

(6)

A．He likes its position and its size, but he doesn't think it's very big.

B．He likes its buildings and its size, but he thinks it's very small

C．He doesn't like its position or its size, but he thinks it's very big.

D．He likes its position and its size, he thinks it's very big.

Section B

Directions: This section is to test your ability to understand short conversations. There are 2 recorded conversations in it. After each conversation, there are some recorded questions. The conversations and the questions will be spoken only once. When you hear a question, you should choose the correct answer from the 4 choices marked A, B, C, and D.

听力原文：W: It was a heavy storm last night, wasn't it？

M: It certainly was. The wind broke several windows. What weather!

W: Do you know that big tree in front of my house？ One of the biggest branches came down in the night.

M: Really？ Did it do any damage to your home？

W: Thank goodness! It is far away from that.

M: I really hate storms. It's about time we had some nice spring weather.

W: It's April, you know. The flowers are beginning to blossom.

M: Yes, that's tree. But I still think the weather is terrible.

W: I suppose we should not complain. We had a fine March after all.

(6)

A．The tree was broken.

B．AI1 the leaves fell down.

C．One of the branches fell down.

D．The tree. was cut down.

Part A

Directions: You will hear 10 short dialogues. For each dialogue, there is one question and four possible answers. Choose the correct answer ― A, B, C or D, and mark it in your test booklet. You will have 15 seconds to answer the question and you will hear each dialogue ONLY ONCE.

听力原文：M: What are you going to wear today, Jane？

W: I'm going to wear my blue dress. I think it looks nice on me.

M: I suppose you can sometimes try on another kind of color for a change.

What color of clothes the woman is going to wear？

A．A brown dress.

B．A blue dress.

C．A suit.

D．An overcoat.