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It's a sad fact: people litter, and trash winds up in our waterways. Thankfully, experts have come up with creative ways to clean rivers and harbors. For example, the Inner Harbor in Baltimore, Maryland, was once teeming with trash. Now a clean-energy-powered wheel called Mr. Trash Wheel is tackling the trash head-on. Garbage floats up a conveyor belt inside the wheel and is deposited into a dumpster. Baltimore's Harris Creek was also full of litter and contributed garbage to the harbor. A second trash wheel, named Professor Trash Wheel, makes sure garbage in the creek is trapped and removed. The Anacostia River in Washington, D.C., faced similar trash troubles. Along came a Bandalong Litter Trap to the rescue. Bandalongs are designed to trap garbage inside a basket before the garbage floats down a river.
Match the problems with their solutions.