For an eliptic curve cryptography using En $(1,6)$ and G$=(2,7).$ B$\text{'}$s private key n$=7.$ 

A$.$ Find B$\text{'}$s Public key P$.$ 

B$.$ A wishes to encrypt the message Pm$=(10,9)$ and chooses the random value k$=3.$ Determine the ciphertext Cm

C$.$ Show the calculation by which B recovers Pm from Cm$.$