I think I got closer Raider (which is my favorite team in any event!).  But good to see you are learning your economics well (I have a degree in the field as well).

I had a problem with a lot of the questions. The one about bottled water, for example, assumed tap water wasn't fresh or not available, whereas here it is both fresh and available.

Entirely predictable.

If you want Bali Belly...go to France and drink their water....from a tap.

That's why they're the world's greatest makers of cheap, crappy wine....

Oh....the hit-rate was about 100 out of 160 .... RMIT Architecture tour.....1973.  [I was one of the 100]....

Well...re bottled water...when it's actually more expensive than petrol it's really getting a little silly....but then the 'liquid' which is far more expensive than blood.....is printer ink.....

I saw some ultra-expensive bottled water in a cafe fridge once... $7.20 for 600ml of peach flavoured [most likely tap] water.  If that's not frickin' criminal I dunno what is.  Worse still, Coca Cola, not satisfied with sales of Coke and other pollutants they stick in bottles, got into the bottled water scam and flogs of mega-litres of the stuff, calling it spring water when we all know the Coca Cola factory is nowhere near a f**king spring.  And I'm sure they truck it in from some distant spring when town water is so cheap/readily available.

Ah, but there's always refills. I rotate two sets of ink cartridges and I have refilled them by a local company @ 25 bucks a time.. that's for the black and colour tanks.  Not only is the quality good, the ink lasts somewhat longer than the Epson stuff.  Same when I had a HP 3-in-one, which drank ink just thinking about the job at hand.

Oh well, if you want to pay big bucks for something I and millions of others pay little or nothing for, it's your choice/money.

Wow, some of you are really humorous. 

So here's the deal, if you are really getting your water for free make sure you boil it for at-least 5 minutes. It won't taste as good due to the oxygen loss but it will be safer. I'm assuming you'll be using wood to boil too so as to make sure the whole process is free.

There's some other filtration or distilling processes you might try too though I'm sure some cost will be involved in setting these up.

I guess you people who live in third world countries don't have clean tap water like we do

I get clean tap water, but the water board puts in additives [fluoride, etc] that make it taste like crap... thus it's boiled and filtered to make it taste like water from the purest spring.

It's not just the fluoride, though.  There are other additives that make the water taste awful, though worse in some areas than others.  My daughter lives about 15 minutes away and her tap water is far nicer than ours.  My sister lives 35 minutes away in the opposite direction and her water is positively foul straight from the tap... so much so I refuse to drink it. 

It depends on the storage facility for each area, I think, and how heavy handed they are with the chlorine, fluoride and other stuff added to keep us healthy.  Frankly, I'd rather take my chances and just have straight, clean water without the additives.