这题长短债的比例低于1.5怎么也用了这个高于1.5公式算'default point呢？问题如下图：
选项：
A. 
B. 
C. 
D. 
解释：
NO.PZ2016082406000090 You are given the following information about a firm. The market value of assets time 0 is 1,000; time 1 is 1,200. Short-term is 500; long-term is 300. The annualizeasset volatility is 10%. Accorng to the KMV mol, whare the fault point anthe stanto fault time 1? 800 an3.33 650 an7.50 650 an4.58 500 an5.83 ANSWER: C The fault point is given short-term liabilities plus half of long-term liabilities, whiis 500+300/2=650500+300/2=650500+300/2=650. The stanto fault point 1 is V−KσV=1,200−6501,200×0.10=4.58\frac{V-K}{\sigma_V}=\frac{1,200-650}{1,200\times0.10}\text{=}4.58σVV−K=1,200×0.101,200−650=4.58. ROA可不可以用（1200-1000）／1000 = 0.2 计算出来？ 如果可以，那么不就可以用另一个公式计算出了吗？ 如果不可以，那么原因是什么呢？ 谢谢
You are given the following information about a firm. The market value of assets time 0 is 1,000; time 1 is 1,200. Short-term is 500; long-term is 300. The annualizeasset volatility is 10%. Accorng to the KMV mol, whare the fault point anthe stanto fault time 1? 800 an3.33 650 an7.50 650 an4.58 500 an5.83 ANSWER: C The fault point is given short-term liabilities plus half of long-term liabilities, whiis 500+300/2=650500+300/2=650500+300/2=650. The stanto fault point 1 is V−KσV=1,200−6501,200×0.10=4.58\frac{V-K}{\sigma_V}=\frac{1,200-650}{1,200\times0.10}\text{=}4.58σVV−K=1,200×0.101,200−650=4.58. 老师，这里面0时刻asset=1000, 1时刻是1200，那分子的asset return 这里为什么不用(1200-1000)，然后再减去fault threshol650?
讲义上没有写乘以1200 这个资产的market value呀， 的公式不是这样的啊
老师，想问一下分母为什么要乘以1200呢
annualizeasset volatility的定义是什么 不太明白1200*10%
