The given question asks about the time difference between two cities, city A located at 30`N 60`E and city B located at 30`N 80`E. To calculate the time difference, we need to understand the concept of time zones.

The Earth is divided into 24 time zones, each approximately 15 degrees of longitude wide. The prime meridian (0 degrees longitude) passes through Greenwich, London, and is considered the starting point for time zones. As one moves eastwards from the prime meridian, the time increases by 1 hour for every 15 degrees of longitude.

In this case, city A is located at 60 degrees east and city B is located at 80 degrees east. The time difference between the two cities would be 20 degrees of longitude, which corresponds to 1 hour. Therefore, the correct answer is option 1 - 80 minutes.

The time difference would be positive when moving from west to east, as city B is located east of city A. It is important to note that time differences can vary, especially when considering daylight saving time or political boundaries that alter time zones.