Đề kiểm tra học kì 2

Đây đâu phải Tiếng Anh? Đây là Toán đốt cháy HIĐROCACBON mà ~

\(nCO2=0,1mol\Rightarrow mCO2=4,4g\)

Do hỗn hợp chỉ bị hidro hóa mà ko làm thay đổi số C nên V Co2 vẫn ko đổi =4.48l

Tham khảo thôi nhé bạn !

That's an airplane. It looks like a normal airplane but it's very modem. It is powered by solar energy. Its speed is very high. Its wings are designed like a panel. It converts sunlight into energy. I think if s a very modem and eco-friendly device. It will be an airplane of the future.

I. Complete the sentences with the question words:

1..HOW MANY.. days a week do you go to school? - 6 days a week.

2..WHAT .. did you watch on TV last night? - The Red Spotted Squirrel.

3.WHY... do you like the Animals programme? - Because I love animals.

4..WHICH.. is your favourite TV MC? - I like Minh Phong in The Gift of music.

5..HOW.. was the Lonely Giraffe made? - I don't know. But I first watched it on TV last year.

6..WHAT.. do you prefer doing in your free time? - Reading books.

7..HOW.. do you think you canlive without TV? - I don't know.

8..HOW.. do you get to school? - By bike.

9...WHAT. is on TV tonight? - "Tom and Jerry".

10..HOW OFTEN.. do you watch television? - Twice a day.

I’m writing from the most beautiful and incredible place in the world that I have ever seen during my 15-year career as a travel writer in more than 70 countries. I’m writing to you from Ha Long Bay in Vietnam.

There is a saying that if you have not visited Ha Long Bay you have not yet been to Vietnam. I say that if you have not visited Ha Long Bay you have not yet seen the most beautiful place in the world.

180 km from Hanoi City, towards the northeast, it takes around 4 hours by bus due to the speed limit, and then you will arrive to Ha Long City and the wonderful Ha Long Bay.

1969 limestone islands of various shapes, sizes, and in different green and amazing colors rise above the sea level in an area of more than 1,500 square kilometers that creates this World Heritage site. Ha Long Bay still retains its historical and culture values.

The guide told me that Ha Long Bay has been twice recognized by UNESCO as a World Heritage Site in 1994 and 2000, and also that Ha Long Bay is in second place in the worldwide competition of the World’s Seven Natural Wonders. I told him that before all, God has given the Vietnamese people this wonder for their kindness.

Ha Long Bay is as attractive and beautiful throughout the four seasons: spring, summer, autumn, and winter. Traveling on small sailboats among hundreds of limestone islands, one may visit the amazing Surprise Cave, the floating fishing village, and see how the locals live are top of the list of things to do here. On Titop Island, one may swim and relax on the beach or enjoy a kayaking program to the nearby Luon Cave and much more.

And what about the important question of where to sleep? Syrena Cruises and other cruises are offering wonderful programs. A luxury cruise from the harbor and across Ha Long Bay, has 34 luxury cabins and suites each with a balcony, as well as restaurants and a meeting room on the 3rd deck. Travelers may experience Asian or Western cuisine, precisely sea food, and also have a session with a massage therapist, unwind in the sauna, take a sunbath and relax on the expansive deck, experience squid fishing, movie night, and a cooking demonstration.

Other attractions during your stay in Ha Long, beside exploring Ha Long Bay itself, if to visit the Royal Park in Halong City, Water Music, a circus performance by dolphins, sea lions, crocodiles, and much more.

The experience of visiting Ha Long Bay is unforgettable, where you will see something that will stay in your mind and eyes for years. You will enjoy meeting Vietnamese people and tasting their delicious food, you will have fresh air all day and night, especially if you wake up early in the morning and watch the sun rise on the deck coming slowly through the islands.

Be sure not to miss visiting Ha Long Bay in your lifetime. Just try to watch images and videos of this stunning and marvelous place and imagine being there experiencing the beauty and kindness of Vietnamese people. You will be booking your trip in no time.

Successfully \(\rightarrow\) Successful

Flash flood

A flash flood is a rapid flooding of geomorphic low-lying areas: washes, rivers, dry lakes and basins. It may be caused by heavy rain associated with a severe thunderstorm, hurricane, tropical storm, or meltwater from ice or snow flowing over ice sheets or snowfields. Flash floods may occur after the collapse of a natural ice or debris dam, or a human structure such as a man-made dam, as occurred before the Johnstown Flood of 1889. Flash floods are distinguished from regular floods by a timescale of less than six hours.The water that is temporarily available is often used by foliage with rapid germination and short growth cycles, and by specially adapted animal life.

Flash floods can occur under several types of conditions. Flash flooding occurs when it rains rapidly on saturated soil or dry soil that has poor absorption ability. The runoff collects in gullies and streams and, as they join to form larger volumes, often forms a fast flowing front of water and debris.

Flash floods most often occur in normally dry areas that have recently received precipitation, but they may be seen anywhere downstream from the source of the precipitation, even many miles from the source. In areas on or near volcanoes, flash floods have also occurred after eruptions, when glaciers have been melted by the intense heat. Flash floods are known to occur in the highest mountain ranges of the United States and are also common in the arid plains of the Southwestern United States. Flash flooding can also be caused by extensive rainfall released by hurricanes and other tropical storms, as well as the sudden thawing effect of ice dams. Human activities can also cause flash floods to occur. When dams fail, a large quantity of water can be released and destroy everything in its path.

The United States National Weather Service gives the advice "Turn Around, Don't Drown" for flash floods; that is, it recommends that people get out of the area of a flash flood, rather than trying to cross it. Many people tend to underestimate the dangers of flash floods. What makes flash floods most dangerous is their sudden nature and fast-moving water. A vehicle provides little to no protection against being swept away; it may make people overconfident and less likely to avoid the flash flood. More than half of the fatalities attributed to flash floods are people swept away in vehicles when trying to cross flooded intersections. As little as 2 feet (0.61 m) of water is enough to carry away most SUV-sized vehicles. The U.S. National Weather Service reported in 2005 that, using a national 30-year average, more people die yearly in floods, 127 on average, than by lightning (73), tornadoes (65), or hurricanes (16).

In deserts, flash floods can be particularly deadly for several reasons. First, storms in arid regions are infrequent, but they can deliver an enormous amount of water in a very short time. Second, these rains often fall on poorly absorbent and often clay-like soil, which greatly increase the amount of runoff that rivers and other water channels have to handle. These regions tend not to have the infrastructure that wetter regions have to divert water from structures and roads, such as storm drains, culverts, and retention basins, either because of sparse population, poverty, or because residents believe the risk of flash floods is not high enough to justify the expense. In fact, in some areas, desert roads frequently cross dry river and creek beds without bridges. From the driver's perspective, there may be clear weather, when a river unexpectedly forms ahead of or around the vehicle in a matter of seconds. Finally, the lack of regular rain to clear water channels may cause flash floods in deserts to be headed by large amounts of debris, such as rocks, branches, and logs.

Deep slot canyons can be especially dangerous to hikers as they may be flooded by a storm that occurs on a mesa miles away, sweeps through the canyon, and makes it difficult to climb up and out of the way to avoid the flood.