A naval engineer is testing an nonreflective coating for submarines that would help them avoid detection by producing destructive interference for sonar waves that have a frequency of 512 Hz and travel at 1480 m/s. If there is a phase change for waves reflected from both the top and bottom surfaces of the coating, what is the minimum thickness of the coating? For sonar waves let nwater = 1.00 and ncoating = 13.5.