tìm a để M lớn nhất M= 4*a/a^2+4

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I was born in Newcastle, a city in the North East of England. Newcastle is on the bank of the River Tyne. It is quite big, with a population of about200,000 people. There is a cathedral and a university. There are five bridges over the River Tyne, which link Newcastle to the next town, Gateshead, where there is one of the biggest shopping centres in the world. A few years ago, the main industries wereshipbuilding and coalmining, but now the chemical and soap industries are important. I movedto London ten years ago and I often return to Newcastle. I miss the people, who are very friendly, and miss the beautiful countryside near the city, where there are so many hills and streams. 11.Newcastle is ____________. A.a city in the North of England B.a city near the North East of England C.a city in the North East of England D. a small town in England 12.The population of Newcastle is ____________. A.200,000 people B.about 200,000 people C.much less than 200,000 people D. much more than 200,000 people 13.Gateshead has one of __________in the world A.the most beautiful countryside B.the largest river C.the most important shipbuilding industries D. the biggest shopping centres 14.According to the passage, writer ________. A.doesn't live in Newcastle any more B.has come back to live in Newcastle C.is still living in Newcastle D. has never returned to Newcastle 15.Which of the following is NOT true about Newcastle A.It is next to Gateshead B.Its main industry now is shipbuilding C.It has a cathedral and a university D. Its people are friendly

VII . Using the words given to make sentences. 46. Quang / brother / walk / movie theater / moment. ______________________________________________________________ 47. Ba / usually / play volleyball / but / sometimes / sailing _____________________________________________________________ 48. The Barkers / never / camping / because / not have / tent. _____________________________________________________________ 49. Where / your parents / moment ? _____________________________________________________________ 50. There / be / house / between / tree / garage. _____________________________________________________________ VIII. Read the passage and choose the correct answer to fill in the gap. I live in a house near the sea. It is ...(51)... old house, about 100 years old and...(52)... very small. There are two bed rooms upstairs...(53)... no bathroom. The bathroom is down stairs ... (54)... the kitchen and there is a living room where there is a lovely old fire place. There is a garden….(5)…... the house. The garden...(56)... down to the beach and in spring and summer.....(57)….. flowers every where. I like alone….(58)..... my dog, Reck, but we have a lot of visiters. My city friends often stay with…..(59)….. I love my house for.... (60).... reasons the garden, the flowers in summer, the weather in fall, but the best thing is the view from my bedroom window. 51. A. a B. an C. the D. any 52. A. It's B. It C. there's D. They're 53. A. and B. or C. but D. too 54. A. between B. next C. near to D. next to 55. A. in front B. front of C. of front in D. in front of 56. A. go B. going C. goes D. in goes 57. A. there are B. they are C. there are D. those are 58. A. for B. of C. on D. with 59. A. me B. I C. my D. I'm 60. A. a B. any C. many D. a lot