Answer:
PART A
Dr Heidegger meant that the old people have already experienced youth and found out the perils of youth so it would be a shame if they wouldn't be better examples to the young ones.
PART B
The warning served as a wake up call for the older people who have experiences of the youth to be role models to them
Step-by-step explanation:
In part À, D Heidegger is reiterating to the older people that with their wealth of experience in engaging in youthful exuberance, they should be able to guide the younger ones so they won't repeat their mistakes.
The warning given by the Dr served as a wake up call to the older people who should know better and act as a shining beacon to the young ones.