Piotr Ratajczak

84.25.Z - Fire protection

33.20.Z - Installation of industrial machinery, equipment, and devices

43.21.Z - Installation of electrical systems

46.64.Z - Wholesale trade of other machines and devices

47.40.Z - Retail sale of information and communication technology equipment

47.54.Z - Retail sale of electrical household appliances

47.69.A - Retail sale of musical instruments and sheet music

47.69.C - Retail sale of other cultural and recreational products, not elsewhere classified

59.20.Z - Sound recording and music publishing activities

60.39.Z - Other content distribution activities

62.10.B - Programming activities

62.20.A - IT consulting and IT equipment management activities

62.20.B - IT consulting and IT equipment management activities

71.20.C - Other technical testing and analysis

74.99.Z - All other professional, scientific and technical activities, not elsewhere classified

82.30.Z - Activities related to organizing fairs, exhibitions, and congresses

85.52.Z - Non-school forms of artistic education

85.59.B - Courses and training for acquiring knowledge, skills, and professional qualifications in non-school forms

85.59.D - Other non-school forms of education, not classified elsewhere

90.20.C - Activities related to the staging of artistic performances