+ Người ta nói rằng khoảng cách từ Trái Đất mất 8 phút ánh sáng tức là " quãng đường ánh sáng đi được trong thời gian 8 phút".

+ Vì ánh sáng đi với tốc độ 300 ngàn cây số mỗi giây nên 8 phút nó đi được quãng đường là :

\(300.000.60=18.000.000\left(km\right)\)

Vậy ánh sáng đi từ Trái Đất đến Mặt Trời mất khoảng 18 triệu km.

Chúc cậu học tốt !

Hey guys, my name is Carolina Trương, to day I'll tell you about my favorite topic "Cycling is a good habit".

As you know, cycling is the greenest form of transportation out there. It is quiet and it is, above all, cheap. You do not need to buy expensive equipment or clothing. Experts calculate that the material and energy used to manufacture a bike are about 5% compared to those needed to make a car. In addition, you are not polluting the atmosphere. Cycling will give you healthier skin. One of the great benefits is that once you start exercising, you are getting a better supply of oxygen to all the major organs, and that includes your skin. Your skin cells will be revitalized and your own supply of collagen will be enhanced. This means that you will be better able to protect against UV radiation, provided you do not forget your sun block.

Finally, cycling have you save money.

Before reading my topic, cycling right now to get more benefits !

Chúc cậu học tốt !