An RSA algorithm uses $247$ as a modulus. The public key for this

algorithm is given by:

$($a$)(7,247)($b$)(4,247)($c$)(2,247)($d$)(3,247)$

$24\mathrm{.}1($a$)($b$)($c$)($d$)$

The calculated private key Ks is given by:

$($b$)(200,247)($b$)(22,221)($c$)(17,247)($d$)$ neither a$,$ b or c

$24\mathrm{.}2($a$)($b$)($c$)($d$)$

For the character B$=66$ the cypher text is given by:

$($a$)51($b$)118($c$)13($d$)19$

$24\mathrm{.}3($a$)($b$))($c$)($d

$[$EEE$8119]$

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For the numerical character $250$ the cypher text is given by:

$($a$)250($b$)20($c$)247($d$)$ neither a$,$ b$,$ or c