地球的半径是多少？

What is the radius of the earth.

youdao

我们知道太阳的质量，太阳的半径,所以可以计算出,太阳的惯性是多少。

We have the mass of the sun, we have the radius of the sun so you can calculate the moment of inertia of the sun.

youdao

一个圆的半径是4厘米，它的面积是多少平方厘米？

The radius of a circle is 4cm, how many square centimeters is its area?

youdao

But the reality that we know from our quantum mechanical model, is that we can't know exactly what the radius is, all we can say is what the probability is of the radius being at certain different points.

我们不可能准确的知道,半径是多少，我们只能说，它在不同半径处，的概率是多少，这是,量子力学。

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