There are six columns in the hall. The bottom radius of each column is 4 decimeters and the height is 5 meters. If the painting fee is 0.5 yuan per square meter, how much is the total painting fee for the six columns?
4 decimeter = 0.4 meter, the total area of painting: 3.14 × 0.4 × 2 × 5 × 6, = 3.14 × (0.4 × 2 × 5 × 6), = 3.14 × 24, = 75.36 (square meter), the total cost of painting: 0.5 × 75.36 = 37.68 (yuan). Answer: the total cost of painting is 37.68 yuan