AK20 means 80% nitric acid + 20% N2O4
AK = Azotna Kislota = Nitric Acid in
NASA
Similar to AK20
A - Alpha
A - Acceleration
A - Aft
A&A - Advertise and Award
A&E - Architectural and Engineering
A&E - Architects and Engineering
A&I - Assembly and Installation
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