Need to know asap for a project

so i pre-recorded a sound on a voice recording app and i need to know how to put that sound over a video. is there an app i can use?

What questions about an audience should be asked during presentation preparation? check all that apply. what does the audience already know about the topic? how will multimedia tools inspire the audience? is the information interesting and engaging? how will this information affect the presentation? will the audience change the message’s purpose? what is likely to interest the audience?