Explanation:

S1 is correct : Meridian is a line that we imagine on the surface of the earth that joins the North Pole to the South Pole and passes through a particular place.  All meridians are of equal length; each is one-half the length of the equator. All meridians converge at the poles and are true north-south lines. All lines of latitude (parallels) are parallel to the equator and to each other. All meridians converge at the poles and are true north-south lines.

2 is incorrect : As the earth rotates from west to east, those places east of Greenwich will be ahead of Greenwich time and those to the west will be behind it.