1. Davidson, who often uses his company's secure mail server, has just lost his private key but still has the corresponding public key. Answer the following questions both with yes/no and by giving a reason for each:
i. Is he still able to send encrypted mails? What about receiving?
ii. Is he still able to sign the mails he sends? What about verifying the signatures of mails he receives?
iii. What must he do to again be able to carry out all the operations mentioned above?