LGPL vs GPL

["Shail Aditya" <shail dot aditya at synfora dot com>]

Hello,
  I am new to this list so please pardon if these questions have been
answered before. But even after some hours of search on the GNU website and
the mailing lists, I cannot find a comprehensive, definitive answer to the
following questions.

Questions:
1. How do I tell what GNU libraries my program is linking with (static and
dynamic)?

2. How do I tell whether these libraries/header files are under GPL or under
LGPL? Does that change from gcc version to version (e.g. from 2.95 to 3.2)?

3. Assuming that all relevant libraries are under LGPL, is there a
distinction (in terms of licencing) between using static or dynamic
libraries?

4. What does it mean for a "work that uses the Library" to have its
executable be brought under LGPL becuase it is linked with the library (LGPL
v 2.1 Section 5) ? Does it mean we cannot charge for the executable or just
that we have to provide the object code at no extra cost so that the user
has the freedom to relink it with a different version of the LGPL covered
library (section 6a) ?

5. The first paragraph of LGPL v2.1 section 6 mentions another exception:

  "As an exception to the Sections above, you may also combine or
link a "work that uses the Library" with the Library to produce a
work containing portions of the Library, and distribute that work
under terms of your choice, provided that the terms permit
modification of the work for the customer's own use and reverse
engineering for debugging such modifications."

Can someone explain or give an example of what is meant by the last
provision.

Thank you very much.

Shail Aditya.