A planet in an elliptical orbit passes three locations P, Q and R where its distances from the Sun are 4×1010m, 6×1010m and 8×1010m respectively. The time intervals required to cover an angular displacement of 5∘ around the Sun at these points are tP, tQ and tR. Which of the following correctly ranks these time intervals?
a) tR<tQ<tP
b) tQ<tP<tR
c) tP<tQ<tR
d) tP=tQ=tR