Respuesta :
Answer:
A two-hour time difference
Explanation:
To understand how Johannesburg (30° longitude) and London (0° longitude) differ, you should appreciate that the longitudinal distance between the two cities defines the time difference and the fact that a longitude of 15 degrees is equivalent to one hour of time difference.
Instead of that London is located at 0° longitude and Johannesburg is located at 30° longitude, the difference in longitudes between them is 30°.
For every 15 arc-minutes in longitude, there is a one-hour difference in time. Consequently, a 30-degree difference means a 2-hour time difference.
As our time in Johannesburg corresponds to that of London in terms of longitude, we will add time instead of subtracting.
By the time it's midnight in Johannesburg, two hours are added to get it to London. For example, if it's 12:In Jo-burg it would be noon, and in London, it would be 2:00 PM.
