In class, the professor taught economics: "What is the primary industry? Feeding cattle and raising sheep. What is the secondary industry? Killing cattle and sheep. What is the tertiary industry? Eating beef and drinking sheep soup." A student asked: "Then what about the cultural industry?" The professor's eyes lit up: "Good question! You are worthy of being my good student." Then he answered: "The so-called cultural industry is just bragging and showing sheep-like appearance!" $ETH $XRP