Will Planes Cross?

Plane A flies at a constant speed of 300 km/h. Plane B is 225 km behind plane A and flies at an initial speed of 420 km/h, but due to fuel limitations, its speed decreases linearly by 30 km/h every hour. Assume both planes fly in horizontal path at safe distance from each other. 

(A) They will cross each other at t = 3 hrs. only
(B) They will cross each other at t = 5 hrs. only
(C) They will cross each other two times
(D) They will never cross each other