定语从句中表地点的from where 与from which 有什么区别?

都填which，在定语从句中，from which=where，都在从句中担任地点状语的成分。
上面两个句子都是非限制性定语从句，先行词分别是the top of the mountain和the window，在从句中作地点状语，又因为是非限制性定语从句，所以填from which。
上面的句子如果改成限制性定语从句也是对的：
1.He climbed up to the top of the mountain where he could see clearly.
2.He appeared out of the window where the whole city came into view.

题目好像不是很完整，see sb./sth.所以第一句缺宾语，如果加上一个宾语，句子完整的话，就该选择from where,这里的where指代的是 from on the top of the mountain, 而on the top of the mountain 用where 替代。
第二题也是同理，from where替代的是from the out of window, 所以都选择where的，
个人想法，答案仅供参考。。。

定语从句中，当先行词指物时，只有介词+which,没有from where的用法，当指地点时介词+which= where，当不能既用介词又用关系副词where。

1.He climbed up to the top of the mountain, from _which___ (which/ where) he could see clearly.

因为此句中的先行词是the top of the mountain，指物，且放在介词from之后，所以用which，from which = where。

2.He appeared out of the window, from _which______ (where/which)the whole city came into view.

先行词rhe window。 理由同第一题。

both are which
没有from where 的形式