Where do you look up latitude and longitude based on zip code? Cause a zip code could be a huge land area, or just a single campus...

>The the formula for the approximate solution is:
>
>One degress of latitude is 69.1mi. One degree on longitude is 69.1mi at the equator and reduces by the cosine of the latitude. Foxpro's Trig functions require radians, so DTOR().
>
>Latdist in mi=69.1 * (lat2-lat1)
>Longdist in mi=69.1*(lg2-lg1)*cos(dtor(lat1))
>total dist=(latdist^2 +longdist^2)^.5
>
>The exact distance formula is:
>
>Distance=3959*acos( sin(dtor(lat1))*sin(dtor(Lat2))+cos(dtor(lat1))*cos(dtor(Lat2))*cos(dtor(Long2)-dtor(long1)))
>
>(from Mailer's +4 users manual)
>
>HTH