World Geography
The length of the tropical years (the time interval between successive occurrences of the spring equinox) is decreasing very slowly as a result of
small, progressive changes in the earth's rotational speed
both (a) and (b)
small, progressive change in earth's orbit around the sun
According to Alfred Wegener, all the major continents formed one giant supercontinent, called Pangaea. About 200 million years ago, the supercontinent Pangaea began to rift.
EXAMIANS