Frog lungs are poorly developed. how does this relate to their skin being thin and moist?

Their skin is thin and moist so they can breath underwater

Their thin skin allows the respiratory gases to readily diffuse directly down their gradients between the blood vessels and the surroundings. When the frog is out of water, mucus glands in the skin keep the frog moist, which helps dissolve oxygen from the air.

The waves slow downn

The answer is "iron"