Question

.. 1. Linear scale is the most accurate method of measuring distances on a map
why
answer correctly​

Answer 1

Answer:

I aim to analyse the accuracy of the various methods of geodesic calculations (distance between two points on Earth)based on the three assumed models of Earth - flat, spherical & ellipsoidal. I need a reliable index to compare my results to measure for accuracy. Will using the WGS84 geoid with Vincenty's formula yield the most accurate results?

Let me focus just on the question of the most accurate way to determine distances on the WGS84 ellipsoid.

The accuracy of Vincenty's method is about 0.1 mm providing it converges. It fails to converge for nearly antipodal points.

Explanation:

My library GeographicLib is accurate to about 15 nanometers and converges everywhere; the algorithm is published in my paper Algorithms for geodesics. I've also published a Test set for geodesics which gives the distances between selected points on the WGS84 ellipsoid accurate to about 0.1 picometers. For more background information see the wikipedia page Geodesics on an ellipsoid