Answers

2016-04-21T11:25:08+05:30

The main difference between local time and standard time is, the local time changes from a place to place, but the standard time remains fixed for the particular country. As per local time, the place/location on the same longitude will have the same local time, but as per the standard time the place on the same longitude will have different standard time.

Prime Meridian: Imaginary line running from Pole to Pole and passing through Greenwich, England. 

Equator: Runs East and West around the exact middle of the globe.
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2016-04-21T13:02:11+05:30

a)
local time changes from a place to place
standard time remains fixed for the particular country. 

The place on the same longitude has the same local time
the place on the same longitude has the different standard time.

b)

Equator separates the Northern and Southern Hemispheres.
Prime Meridian separates the Eastern and Western Hemispheres.

Equator is at 0° latitude.
Prime Meridian runs through Greenwich and is at 0° longitude.
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