Answer:
To calculate the straight-line distances between cities, we can use the haversine formula, which takes into account the curvature of the Earth. We'll need the latitude and longitude coordinates of each city. Here are the approximate coordinates:
a. Johannesburg, South Africa: -26.2041° S latitude, 28.0473° E longitude
Durban, South Africa: -29.8587° S latitude, 31.0218° E longitude
b. Rio de Janeiro, Brazil: -22.9068° S latitude, -43.1729° W longitude
Cape Town, South Africa: -33.9249° S latitude, 18.4241° E longitude
Using these coordinates, we can plug them into the haversine formula to calculate the straight-line distances. However, I'll provide the result without the detailed calculation:
a. The straight-line distance between Johannesburg and Durban is approximately 484 kilometers (301 miles).
b. The straight-line distance between Rio de Janeiro and Cape Town is approximately 5,950 kilometers (3,698 miles).
