meaning of "obvious statement" and "the form of lengthy"

Solution 1:

In the first example, the "statement" is that "the internet works as a contemporary CV". The writer thinks that it is obvious that this statement is true.

As to your second example, the words "form of lengthy" don't belong together. The book "makes demands of its reader". What form do these demands have? "Lengthy exercises to be done". (The word "lengthy" could be removed from the sentence, and it would mean nearly the same thing.)