question_answer

The angle of elevation of a jet plane from a point Q on the ground is\[\mathbf{60{}^\circ }\]. After a flight of 20 seconds, the angle of elevation changes to\[\mathbf{45{}^\circ }\]. If the Jet plane is flying at a constant height of 3000\[\sqrt{\mathbf{3}}\] m, then find the speed of the jet plane.

A)  295.18 km/hr                                                   

B)  395.28 km/hr

C)  255.20 km/hr                                       

D) 345.38 km/hr

E) None of these