Read the passage below and choose one correct answer for each question.

Today’s urban cities are practically bursting at the seams. According to research from the United Nations, 54 percent of the world’s population lives in urban areas, a percentage that is expected to increase to over 66 percent by 2050. In fact, India alone is projected to add 404 million urban dwellers to its population by 2050. This rapid growth of the urban population has caused daunting problems for city planners, such as overcrowded roads, excessive energy consumption and unemployment. Therefore, to build more sustainable cities and accommodate the growing number of residents, many city leaders are turning to the Internet of Things (loT). The IoT has forever changed the way urban cities operate. Cities that were once detached and inaccessible are now intelligent and highly connected. From Amsterdam to Seoul, cities are launching smart city projects to help improve quality of life for residents and better support the environment. According to research from HIS Technology, there will be at least 88 smart cities globally by 2025, up from 21 in 2013. San Francisco, for example, provides more than 100 charging stations in various locations to promote the use of hybrid and electric cars to reduce harmful greenhouse gas emissions. Copenhagen is also taking advantage of the IoT to improve environmental protection and reduce road traffic by developing smart bikes equipped with sensors that generate data on air contamination and traffic congestion. The possibilities afforded by the IoT are endless; however, designing smart cities requires comprehensive technology infrastructure that is capable of capturing and processing large amounts of data quickly and securely - which is where 4GLTE comes into play. The future looks bright for urban cities. Soon they will be able to do things that only sci-fi enthusiasts could dream of before, like monitoring bridge conditions using intelligent sensors and conserving energy by automatically dimming street lights when no one is around.

Today’s urban cities__________.

A. account for 66 percent of the world’s population

B. have more 404 million dwellers by 2050

C. are in fact extremely crowded

D. are bursting around the world

Cho hình bình hành ABCD. Gọi I và K lần lượt là trung điểm của AB, CD. Đường chéo BD cắt AK, AI lần lượt tại M, N. Chứng minh rằng: AK//CI

Cho hình bình hành ABCD có H, K lần lượt là các chân đường cao kẻ từ đỉnh A,C xuống BD. Gọi O là trung điểm của HK. Chứng minh A, O, C thẳng hàng.

Cho hình bình hành ABCD. Gọi E là trung điểm của AD, F là trung điểm của BC. Chứng minh BE = DF và A B E ^   =   C D F ^ .

Cho hình chóp S.ABCD có đáy là hình thang vuông tại A và B, A B   =   B C   =   2 ,   A D   =   4 ; mặt bên SAD nằm trong mặt phẳng vuông góc với đáy và có diện tích bằng 6. Thể tích khối S.BCD bằng

A. 6

B. 18

C. 2

D. 1

Mật độ cá thể của quần thể sinh vật là

A. tỉ lệ đực và cái trong quần thể.

B. số lượng cá thể của quần thể trên một đơn vị diện tích hay thể tích.

C. số lượng cá thể có trong quần thể.

D. tỉ lệ nhóm tuổi trong quần thể.

Read the passage and choose the best answer.

You can recycle many types of glass. Glass food and beverage containers can be reused and recycled many times. (In fact, only bulbs, ceramic glass, dishes and window glass can’t be recycled.)

Glass is made from soda ash, sand and lime. If it’s thrown away, it stays there indefinitely because glass never breaks down into its original ingredients. To be recycled, glass is sorted by color, crushed into small pieces and melted down into a liquid. Then, it is molded into new glass containers.

Which of the following can be recycled?

A. glass food and beverage containers

B. bulbs

C. dishes and window glass

D. ceramic glass

Tìm giới hạn  F = lim x → - ∞ x 4 x 2 + 1 - x

A.  + ∞  

B.  - ∞  

C.  4 3  

D. 0