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Traveling in the Future

These days, if you want to travel from New York to Beijing, the flight takes about 16 hours. You also have to wait at the airport, and sometimes you have to transfer onto a different airplane. If you add all of that extra time, the trip takes at least 20 hours. But in the future, the trip from New York to Beijing might only take two hours.

Right now, a private company is developing something called ET3. ET3 stands for “evacuated tube transport technology”. Here is how it works. A tube goes all the way from New York to Beijing. The tube is only a few meters wide. Capsules move through the tube. Six people can sit in one capsule. The capsules use electricity instead of gasoline. For international travel, the capsules can travel at about 6,500 kilometers per hour. That is much faster than airplane - most modern airplanes usually only fly at about 800 kilometers per hour.

So how is this possible? How can these capsules travel so fast? The answer is that there is no air inside the tube. When airplanes fly, they have to move through the air. The air slows the airplanes down. Because there is no air in the ET3 tubes, the capsules are able to move at a very high speed. Besides, the capsules are quite light. They only weigh 183 kilograms.

There are other advantages to ET3. Because it uses electricity, it is quite clean. In addition, it is much quieter than airplanes and cars. Finally, ET3 tubes and capsules don’t require very much building material.

Of course, ET3 doesn’t exist yet. The technology is still being developed. Developers still have to solve a lot of problems. The biggest problem is that right now, ET3 would be far too expensive. In order to make ET3 cheaper, we will need much better technology.

It is exciting to think of how ET3 will change travel in the future. Maybe someday, you will be able to have lunch in New York and dinner in Beijing.

Overcrowding is a pressing issue that affects many communities around the world. It refers to a situation where the number of people living in a particular area exceeds its capacity. This can occur due to rapid population growth, urbanization, and migration, coupled with insufficient housing infrastructure. The effects of overcrowding are far-reaching and detrimental. Firstly, it poses significant health risks as it increases the likelihood of the spread of diseases. Additionally, overcrowded areas often experience higher crime rates, as the lack of space and resources can lead to heightened tensions. Moreover, overcrowding puts a strain on public services and resources, such as schools, hospitals, and transportation systems. To address this issue, it is crucial to implement effective urban planning and development strategies, along with initiatives to provide affordable housing. Furthermore, improving transportation systems can help distribute the population more evenly. Lastly, population control measures should be considered to manage the growth rate. In conclusion, overcrowding is a complex problem that requires collective efforts from individuals and governments. By taking proactive steps, we can create healthier and more sustainable communities for future generations.

$HaNa♬☘$

Bài 3:

Số học sinh kém là:

40-8-10-20=2(bạn)

Tỉ số phần trăm giữa số học sinh giỏi so với lớp là:

8:40=20%

Tỉ số phần trăm giữa số học sinh khá so với lớp là:

20:40=50%

Tỉ số phần trăm giữa số học sinh trung bình so với lớp là:

10:40=25%

Tỉ số phần trăm giữa số học sinh yếu so với lớp là:

2:40=5%