Check these, please!

[Anonymous]

Hi,
Please check these sentences and correct them.
1-1. (In) So/As far as calculus is concerned, Helen is [the best, next/second to none].
1-2. When it comes to calculus, Helen is [the best, next/second to none].
2. You are a piece of work. [What does this sentence mean? When do we use this expression?]
3. Are you free on Friday evening? or Will you be free on Friday evening?
Thanks a million.
Ann

[Rusty]

1-1. (In) So/As far as calculus is concerned, Helen is [the best, next/second to none]. (In so far as/so far as/as far as...OK. <strike>in as far as</strike>)
1-2. When it comes to calculus, Helen is [the best, next/second to none]. (OK).
2. You are a piece of work. [What does this sentence mean? When do we use this expression?] (I am guessing that it's the slang meaning that you want. A search of the Internet brings up the literal meaning, i.e. a piece of artwork, music, a craft, etc. and quotes from Shakespeare's Hamlet, "What a piece of work is man, how infinite in faculties, etc." If somebody calls you a piece of work it is a gentle chiding. They feel a mixture of amusement and exasperation at your behavior, ideas, etc.)
3. Are you free on Friday evening? or Will you be free on Friday evening?(Both OK).