Answer: Larger than, 2300 BC, 650 BC.
Explanation: Just look at the given chart, and compare it with the given question and given options offered. From the chart it can be seen that in the period from 2800 to 650 BC the size of city was larger than the size of empire. The chart also shows that the size of the empire was larger than the size of the city in 2300 BC, although the size of the empire was also slightly larger in the 800 BC. But then the size of the city was not smaller than in most other times on the chart, as stated in the given text of the question. In 2300 BC the size of the city was smaller than it was in most other times. The largest city appeared around 650 BC, also seen from the chart.