If you have a good understanding of your audience, you can probably predict the key questions and concerns they are likely to have. You may not be able to give the audience the answers they would like to hear, but at least you should be ready to discuss the things they care about most.
Many speeches these days are followed by a question and answer session which allows the audience to raise any issues they do not feel have been fully dealt with by the original speech – but it is better for the audience if the original speech deals with those concerns, as it shows that they have been thought through rather than addressed “on the hoof”.
Predicting questions and concerns should be straightforward. If you are in a position to address a larger group of people, then the chances are that you have knowledge of the issues that affect them and how these can be addressed. It is also possible to take a sounding from people “on the ground” as to what is concerning them. It may well be that you share those concerns and have given some thought to addressing them.
If you can speak intelligently and emotionally about the issues that concern your audience, they will have a lot more trust that you can help provide solutions to problems, and that their position is understood and respected.
It may help before delivering a speech or presentation to make a list of the five most searching questions you expect people to have. Your presentation should then concern itself with answering those questions as well as delivering your own standpoint.
When delivering the speech it is helpful to pay tribute to the fact that these concerns exist, by saying something along the lines of: “And before I go any further, I would like to raise an issue that I know has been foremost among the minds of many here…”. As the audience is giving you their attention, it is simply reasonable that you make clear that they, too, have yours.