Presentation and Pitching Skills for Entrepreneurs
immadsnewworld.com
immadsnewworld.com
Nothing kills a presentation faster than someone in the audience asking "where did you get that number / equation / data?" or "why did you choose that technology / layout / structure?" and the presenter not knowing. People aren't going to trust you with their money if you don't understand what you're telling them well enough to answer probing questions.
It suggests that you have sufficient confident mastery of the field to know that you don't know the answer off the top of your head but that somebody on the team has a satisfactory answer, suggests you know the answer isn't a threat to you, and allows you to control the pacing and direction of the presentation.
(Of course, they are bad answers to the basic question about provenance asked by the GP - if someone was asking you where you got Graph X and you don't know, telling them that you'll talk with them later will be treated as the dodge that it is, not as a compliment.)