Meaning of 流石 in Japanese

さすが、お嬢様。自由奔放な生活をしていたわけじゃないんだ。
Just what you'd expect of a young lady, you certainly weren't left to live as you pleased.

さすがに偉大な学者だけあって、彼はその問いに容易に答えた。
Like the great scholar that he was, he answered the question easily.

さすがは、王子様ですわね。きっとただならない傑物の素質をお持ちなのですわ。
Isn't that just what you'd expect from the prince? He certainly has the character of a truly great man.