Question 1
At the same time, car X leaves city A for B and car Y leaves B for A. Their individual speeds are constant, and Y is 20 km/h faster than X. They first meet at C after 30 minutes. On reaching B and A respectively, they immediately turn back and meet for the second time at D. Given $AB=2CD$, find AB and both speeds. Answer as (AB in km, X speed, Y speed in km/h).