Question

when the Prime Meridian of Greenwich has the sun at the highest point in the sky, all the places along this Meridian will have first moon or mid-day second morning third midnight​

Answer 1

Explanation:

A prime meridian is a meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°. Together, a prime meridian and its anti-meridian (the 180th meridian in a 360°-system) form a great circle. This great circle divides a spheroid, e.g., Earth, into two hemispheres.

Answer 2

ANSWER:

All the places along the Prime Meridian will have first noon.  

EXPLANATION:

      The prime meridian is the longitude of 0°. It passes through Greenwich near London. "The earth rotates" from "west to east". However, the sun rises and "sets in the opposite direction" with earth's rotation, that is from east to west as the sun moves, everyplace on earth has its sun rise time, sun set time and noon.

    When the sun in the sky casts its shadow on the earth's surface, we can measure time. While the sun is at the middle in the sky, it is the crossing the meridian. Thus, it is noon at that time.