The following two statements pertain to contour lines.
S1: A contour line must necessarily close upon itself, within the limits of the contour map.
S2 : The contour lines cross the ridge line or valley line at right angles.
Identify the validity of statements as true or false.
1
Both statements S1 and S2 are true.
2
Statement S1 is false, but S2 is true.
3
Statement S1 is true, but S2 is false.
4
Both statements S1 and S2 are false.