[linux-lvm] How do I do RAID 4/5 *and* LVM?

[Dave Newman <newman uci edu>]

Hi --

I have four 160 GB IDE disks, and wanted to install software RAID 4/5 
*and* LVM, and wanted to ask a couple of brief questions:

a) Do I need LVM if I want to see a single partition (or can RAID do 
this for me)?

b) Do I first install RAID, then LVM?  Are there any difficulties with 
these installs?  (I have already successfully done LVM on its own)

c) Are there any reasons why I shouldn't use both RAID and LVM?

Thanks in advance,
Dave