According to Keppler’s third law of planetary motion
1
Every planet moves around the sun in an elliptical orbit with the sun at one of the foci.
2
Arial velocity of planet revolving around sun remains constant
3
Arial velocity keeps on changing and it is maximum at apogee
4
The square of the period of revolution (T) of any planet around the sun is directly proportional to the cube of the semi-major axis of the orbit