Which of the following statement regarding centrifugal compressor is true?
1. Conversion of dynamic pressure into static pressure takes place in the volute casing due to its convergent shape.
2. In multi stage centrifugal compressor, the width of the blades reduces progressively in the direction of flow.
3. In multi stage centrifugal compressor, the width of the blades increases progressively in the direction of flow.
4. Multi staging in centrifugal compressors is commonly used for high refrigerant capacity applications.