已知$△ABC$的外接圆半径为R，角$A$、$B$、$C$的对边分别为$a$、$b$、$c$且$2R\left({\sin }^{2}A-{\sin }^{2}C\right)=\left(\sqrt{2}a-b\right)\sin B$，那么角$C$的大小为        （      ）                             

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    Traveling by bicycle is a very popular means of transportation throughout China. China has a huge population, and it is said that there is at least one bicycle for every two people within the country. Of course, many people in China ride bicycles purely for sport or exercise, but it's also a much more commonly accepted means of everyday transportation, as compared to countries such as the United States.

    If you are living for a long period of time in China, chances are you will want to purchase your own bicycle so that you can use it whenever you want for transportation or just for the enjoyment of riding. Even if you don't use a bicycle for everyday transportation, owning one can be a great way of enjoying some of the trails in the rural areas, just for fun. However, if you are just visiting China, renting a bicycle can be a more convenient choice.

    It is important to choose the correct bicycle for your use. You'll find that in China, the one-speed style of bicycle is extremely popular. These bicycles are great if you want to ride around in the city to see the sights. They are quite comfortable and easy to ride. You can often rent a bicycle for an entire day for around $15.

    However, if you wish to ride on some of the rural paths, a mountain bike style would be a better choice. They are great for different kinds of road surfaces, providing for a safer ride. If you are planning to have a desire to tour and still be able to carry packages with you, then a touring bike would be the best choice. These are generally the most expensive to rent, but are extremely handy for carrying packages and even some of your luggage along with you.