Answer:
userB will use his/her private key.
Explanation:
The steps involved in using asymmetric cryptographic algorithm are as follow:
1. Each user generates a pair of keys to be used for the encryption and decryption of messages.
2. Each user places one of the two keys in a public register or other accessible file. This is the public key. The companion key is kept private.
3. If UserA wishes to send a confidential message to UserB, UserA encrypts the message using UserB's public key.
4. When UserB receives the message, she decrypts it using her private key.
Answer: Add more cells in series.
Explanation:
Adding more cells in series will add voltage which will increase the power.
Have you tried turning it off and back on.Try that if that does not work then try debugging it