For the first question, now the trick is here that u will realise that the lorry takes 2.5h to reach the midpoint between X and Y, so to get the total distance between X and Y, just remember to multiply by 2. Once we get the total distance, we can find out the car's original speed. The time taken for the car to reach the midpoint is 2h since it starts moving at 9am and met the lorry at 11am at midpoint. Remember to increment the car's speed after that then find the time taken to travel half of the total distance between X and Y and you are done