版上700+的神人们好，
有个问题想请教大家，就是在比较结构中，more than/as..as的摆放位置
比方说像pp这题
Officials at the United States Mint believe that the Sacagawea dollar coin
will be used more as a substitute for four quarters rather than for the
dollar bill because its weight, only 8.1 grams, is far less than four
quarters, which weigh 5.67 grams each.
B) more as a substitute for four quarters than the dollar bill because it
weighs only 8.1 grams, far lighter than
C) as a substitute for four quarters more than for the dollar bill because it
weighs only 8.1 grams, far less than
我知道这题是比较受词，所以要补出介系词
我想问的是more放在as a substitute for的前面跟放在后面的差别是什么?
另外还有一题
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.
(B) as little risk as one chance in a million of causing
(D) a risk as little as one chance in a million for causing
像是这题a risk放在as...as里面跟放在外面的差别是什么？
我知道网络上大部分解题，包括曼哈顿都好像不是以这个为解题点
但我真的很想了解这部分的差异是什么~还请大家帮忙解答，谢谢!