A 24-year-old Dutch college dropout has designed something that just might help save the oceans from plastic trash. A man named Boyan Slat raised more than $30 million to build an ocean-cleaning machine. He started a nonprofit in the Netherlands called Ocean Cleanup. More than 60 engineers and scientists work there. Slat’s machine is basically a polyethylene pipe 4 feet in diameter and almost 2,000 feet long. It will form a U on the ocean’s surface and move slowly through the water. The pipe and a skirt that hangs below it will capture plastic on the water and debris almost 10 feet below it. Will it work? Will it be dangerous to fish and marine animals? Will a Pacific storm tear it apart? No one knows the answers.