How many is the difference between the minimum and maximum population estimates around Lake Petén Itzá in 1697?
return Lake Petén Itzá ;return population estimates of #1 ;return #2 in  1697 ;return the  highest of #3 ;return the  lowest of #3 ;return the  difference of #4 and  #5
['select', 'project', 'filter', 'aggregate', 'aggregate', 'arithmetic']