Hello how do I solve these 3 questions?

1. In RSA cryptography, if the public key (25,551), find the private key. (15 marks) 2. In RSA cryptography, with the public key given and private key found respectively in Q1), find the encrypted message (cyphertext) for the original message encoded as 15 . (14 marks) 3. In RSA cryptography, with the public key given and the private key found in Q1), find the encoded numeric code for original message (decrypted message) for the cyphertext text 298