Therefore being exposed to 1 Sievert for a second (the real unit behind the sievert is the J/s, which is equivalent to Watts) is the same as being exposed to 1 milisievert for 1000 seconds, or 1 microsievert for 10^6 seconds.
Nope. Sieverts are J/kg. "1 millisievert for 1000 seconds" makes no sense, but "1 millisievert per 1000 seconds" does.
The easiest way to figure the cost of living is to take your income and add ten percent.