more than three cities = shrines (50% culture boost per religion) 9 cities total for a shrine in each of the three culture cities as each shrine requires three temples
...
The GA's help to speed you up for a few turns at the end, but not too much (depenable how much culture are you generating).

) of how much money would be minimal but probably acceptable investment to get up to speed on time.
... hmmm... lots of money in any case, so I guess more Great Merchants, as early as possible you get better it is, you can't have too many of those it seems, 5 of them at least would be very very helpful... 
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