Ask him to point you where the rear motor mount is, and ask how he became a tech. After he's finished pointing out the wrong thing tell him you'll never come back again for his sheer idiocracy.
yes i am serious.and if you don't know anything about cars,don't comment my quotes.i know what i am talkin' about.i'm not saying you don't.but yes,for better vibration control,car manufacturers have used viscous fluid technology to better their motor mount vibration control characteristics