JEE Advanced Model Paper 13 with solutions for online practice

A passenger car is driving on a level highway behind a truck. A stone got stuckbetween double tyres of the rear wheels of the truck. Both the vehicles have aspeed 54 km/h in same direction. At what may be the distance(s) of separationshould the car maintain with the truck, so that the stone will not strike it if flies outfrom the double tyres? (Take g = 10 m/s2)