1. Why is apnm a problem to (a) individuals and (b) copporation?
2. Is requiring e-mail service providers to pay a fee (price) for bth
spam and legitimate e-mail a solution to spam?

Well, the problem is uch worste for people who use dial up for obvious
reasons. Otherwise, it justtakes time to sortthrough, jurts your email
quota, andoften timesthe content isfraululent or otherwise criminal. 
it also obscures legit emails.  Further, filters used to block spam
can also block/reroute legitimate emails.

CHarging a fee is a plausible solutio, but it also problematic.  One
thing people often complain about is the digital divide (the fact poor
people have less access thanthe well off), charging for incoming or
outgoing emails will further this divide. it would als be problematic
for children and such to send email as they would have little
mechanism to pay for it.

Perhaps a better solution would be to require a username and password
to send an outgoing email. (Most ISP's do ot require a password to
send an outgoing email).  (I am referring to the use of amn
application like outlook, obviously webmail requires a password.)

Spam clutters mail boxes, wastes time deleting it, has annoying or
offensive content, wastes infrastructure. This last issue also impacts
corporations since they have to battle spam and invest in staff and
infrastructure to handle the volume and to try to keep the volume
down. One way to look at spam is as part of information war, like junk
mail.  One wonders what would happen to the Post Office's finances if
they raised the fee on junk mail?  Would it reduce the trash in land
fills and save a few trees too?  These benefits would not accrue for a
fee on spam given the nature of the internet.  Would the big spammer's
just become pirates and set up their servers and systems outside any
regulatory structure like rogue radio stations used to do?