1 дискета
2cd rom
3 dvd rom
4 флеш
5 жесткий диск
PYfy9pX4YibdfKzE8dnbSXaP3D5sbZenWQXx+TzottBxmrnKP4dS39zDFCHeytaxQuaxO6+SihcUhSqF6PmmxN3GxGIIAPLiSxjqjTtSHbvo7htEBwkC9DrKA9nK9xIOxPRcjpd6DAdMG0SkqPbK1+57wXgl2KsD43bDyI91iNHZGVEFuJjW2WjoZmDZOb/rVd7R9AqyWfNwqgLu5n0s8oZKpT55zvtPlOdDo6CM93h3C9G55Qj17fBXO/NNywpSzMGUqCxZha8Dm9QprL4Amawdo2pnCyu31Kn+Zny692acWR8k+IjeIoeL9HS7GGpxomAYoUcl2QOl2meKVWiovxtHmLKNooQK1Hc8yqvu293YHqgzQp3rHNgJxPJfiQnUmlYXGvOGZLk6vEUXIiesvdftDsCS/8Ae6YiLr8HWExGez9YXrworoX46BqS86+EFy3m8zwgu1fA9z61qLUP90KYw8KxlJJDWAThAVGrADHEsoHJ35+216/jwx5ruS3xgPOL83Vy5P1bL884jUiefVsuhprgR7C75lvy2ZCUYolQ=
250*8:2000= 1 бит информации несет каждый символ.
Раз 1 бит, значит символов 2^1=2.