Question: need help??? For the five-digit zip code, the first four digits can be any of the digits 0-9 and the fifth any of the digits 1-8. For the plus four zip code, the first three digits can be any of the digits and the fourth any of the digits 1-9.\n(a). How many possible five-digit zip codes are there?\n(b). How many possible plus four zip codes are there?\n(c). How many possibilities are there in all, including both the five-digit zip code and the plus four zip code?

Answer: a. 10*10*10*10*8=80,000 possible combinations\nb. 10*10*10*9=9,000 possible combinations\nc. 18,000*9,000=720,000,000 possible combinations
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