prep164（2008）链接 关于as的用法，求教

cherry1123lan

这道题目我是懂的，但是它链接的我不懂
Mixed with an equal part of water, ethylene glycol, a compound commonly used as an automotive antifreeze, is effective at temperatures as low as –30 degrees Fahrenheit.

temperatures as low
temperatures so low
as low temperatures
as few            
as little

类似题链接：
prep 2-9 The Environmental Protection Agency frequently puts mandatory controls on toxic substances that present as little risk as one in a million chances to cause cancer.
(A) as little risk as one in a million chances to cause
(B) as little risk as one chance in a million of causing
(C) as little risk as one chance in a million that it will cause
(D) a risk as little as one chance in a million for causing
(E) a risk as little as one chance in a million for it to cause
Key: B
如果D和E改成a risk as little as one chance in a million of causing也就对了
1. 比较结构as adj. a noun. as... ：
as....as之间是可以加 adj+noun的，不过好像只限于几种形式(张振邦)：
as+adj.+不定冠词+单数可数+as   I haven't seen as old a car as this for years.
as+adj.+零冠词+不可数名词+as   对应 prep2-9 (见类似题链接)
as+adj.+零冠词+复数可数名词+as I don't smoke as expenesive cigarettes as those.
2. as adj. (a) noun. as = (a) noun. as adj. as，其中第一个as是adv. 什麼時候有a 什麼時候沒有？


根据考点上说的话，那risk是不可数的， as little risk as。。。是ok，那为什么可以a risk as little as one chance in a million of causing，as little risk as...=risk as little as才对吧。。？

酷莎白

我还有一个问题：原题C选项中说at后面缺少名词作宾语，as low temperatures as-30 degrees Fahrenheit不能做宾语吗？可同样是as adj. a noun as...结构，I haven't seen as old a car as this for years.这边as old a car as this year为什么可以做宾语？