17.11 a piece of corroded metal alloy plate was found in a submerged ocean vessel. it was estimated that the original area of the plate was 800 cm2 and that approximately 2.6 kg had corroded away during the submersion. assuming a corrosion penetration rate of 200 mpy for this alloy in seawater, estimate the time of submersion in years. the density of the alloy is 7.9 g/cm3