Moon enters penumbra: instant of first external tangency of moon with the penumbra.

半影食始：月球刚刚和半影接触，这时肉眼觉察不到。

Then finally, the final step is to find what is the tangency line that goes through the riskless rate.

在最后，最终的步骤是找出一条，穿过无风险收益率的切线。

Now, he's using a much longer sample than I did, so he's not going to get this tangency portfolio that I did.

他的样本跨度比我的要大多了，所以他得出的切线资产组合会和我的不同。

Although smooth, there is a characteristic "break line" of tangency denoting where the circle meets the line.

虽然平滑，但它存在着一个特点，就是圆弧和直线相接的地方会有一个曲率变化上的断裂。

The asset pricing model — and this is critical — assumes everyone is rational and holds the tangency portfolio.

资本资产定价模型是非常重要的模型-，假设每人是理性的，并持有切线资产组合。