Video Audio Synchronization

Hi, i have made 5 videos and then ordered the professional voice over from audio company but now i cannot synchronize the video with new sound your job will be to put it all together so the videos go with the new sound these are forex training video i will provide these 5 videos, all of them have my voice over i will also provide new audio files, full lenth plus, 1 minute pieces for each video (i dont know which one will be better for you) your job is to put a new voice over my voice so it all looks good etc screen recoder is neccessary i need it done asap your bid is for 5 videos around 55 minutes long thanx, greg