7. Indicate millionaire cities.

Analysis of the map:

The map shows various dots, some of which represent cities. However, there are no explicit labels or a legend that distinguishes 'millionaire cities' (cities with a population of over one million) from other settlements. Without such a distinction or accompanying data, it's impossible to identify them solely from the map.

Task 7: Indicate millionaire cities.

To complete this task, the map would need to either have specific symbols for cities with over one million population, or the names of these cities would need to be provided, allowing for external verification of their population status. This information is not available on the map.

Conclusion: I am unable to complete task 7 based solely on the visual information present in the image.