Matthew biked for 4 days across an island. He started at the shoreline, which is at an elevation of 0 feet. At the end of day 1, Matthew had gained 3,200 feet in elevation. At the end of day 2, he had gained an additional 1,830 feet in elevation.On day 3, Matthew biked down to the shoreline on the other side of the island, which is also at an elevation of 0 feet. How many feet in elevation did he lose on day 3?