Permanent hardness of water cannot removed by

پانی کی مستقل سختی کو کس وجھ سے دور نہیں کیا جا سکتا

Adding caustic soda

Distillation

Addind soda

Boiling

Explanation

Answer:

The permanant hardness cannot be removed even if it is boiled. The permanent hardness of water can be removed by the gun's palm tit method, ion exchange resin method, and cleaning soda method. This means that the permanent hardness of water cannot be removed with boiling water.