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Trucks arrive randomly at the average rate of 5 per hour. A team of two warehouse workers can unload trucks at the rate of 6 per hour. Each warehouse worker receives $20 per hour. Each idle truck will be charged $100 per hour penalty for waiting. What is the expected total costs? (Total costs - Labor cost + Penalty of idle truck) $456.67 perhour $416.67 per hour 5164.17 per hour $13000 per hour