8、 The collection efficiency of a cyclone is 45% over the size range 0-5 mm, 80% over the size range 5-10 mm, and 96% for particles exceeding 10 mm. Calculate the total efficiency of collection for the following dust: 50% 0-5 mm, 30% 5-10 mm, 20% above 10 mm. (A)86%(B)71% (C)53% (D) 65.7%