Rivers that plunge over escarpments create large waterfalls known as rifts. True False

F=31 because you subtract 39-8

From my point of view, the answer would be a.

Each meridian forms half of a great circle, assuming a spherical earth. meridians intersect lines of latitude (parallels) at right angles. the spherical earth is divided into  360 degrees   east-west. lines of longitude range from 0° to  180° to the east and from 0° to -180 ° to the west of the prime meridian.