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  | Sl No | Parameters | Range of Variables |  
  | 1 | Time of grinding | 2, 3, 4, 5 and 6 |  
  | 2 | Mill speed | 23, 41, 66 and 82 rpm |  
  | 3 | Size of balls | 1", 1/2", 1/3" and 1/4" |  
  | 4 | Quantity of feed | 50, 100, 150, 200, and 300 |  
  | 5 | Feed size | –1/2" + 1/4" –1/4" + 1/8"
 –1/8" + 1/16"
 –1/16" + 1/32"
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