Question

A girl is standing at a roof of 15m tall building throws a ball with initial speed of 10 m/s 60 degrees above the horizontal line. At that moment her dog is on the ground at the distance D from the building and starts running towards the building wall with constent speed of 5 m/s how far from the building was the dog before it started

Answer 1

I think D=0 is the right answer

if yes, I will post the solution