Correct answer
D. Aluminium, copper and manganese
Explanation
The correct answer is Aluminium, copper and manganese.
The type of bacteria which is active in trickling filter during biological treatment of sewage is the ________ bacteria?
The minimum number of phases that can exist in a system is________?
________ is the hardest material out of the following?
The main function of primary air in pulverised coal fired burner is to________?
A coal having higher volatile matter content will necessarily have lower________?
Diamagnetic materials are magnetised________?