Question

You are getting ready for a short daytime outing on the water. what is the most important information to tell a responsible person?

Answer 1

 the most important information to tell a responsible person would be: where and when
Whenever you went to an outing on the water,  you need to provide this two information to someone that you could trust. This information will help other people to find you in emergency situation (you're trapped in the open sea, etc)