Why processing of fish and shellfish is neede?

 The operations of importance in fish processing are washing, degutting, salting, fermentation, drying, and smoking. These operations contribute to the development of flavor, texture, color, and improved storage characteristics of the products.

Explanation:

sulfur dioxide

explanation: acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. these substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.