our environment

Consider the following statements about pollution I.Pollution is an undesirable change in physical ,chemical or biological characteristics of air ,land ,water or soil II.the air act was amended in 1987 to include noise as air pollutant III.In order to control environmental pollution the government of India has passed the environment protection Act ,1976 to protect and improve the quality of our environment Which of the statements given above are correct?

Which two action plane initiated by the ministry of environment and forests to save major rivers of our country from pollution ?

The main physical barrier of our body which prevents entry of micro-organism from environment is :-

We are driven to _____the environment by our curiosity and our need for sensory stimulation