Montags and Clarisse's realtionship is weird. If she had not died I think they would have become a lot closer throughout the book. Clarisse seemed to bring out a different side of Montag. They way she would ask him questions and make things for him.
JKS stands for Java KeyStore. It is a repository of certificates (signed public keys) and [private] keys. You can export a certificate stored in a JKS file into a certificate file. You can use the keytool utility found in Java distributions to maintain your JKS trust and key repositories.
Sometimes it happens that the files of the .JKS type a wrong program is assigned. This can sometimes be the result of the action of hostile programs such as viruses and malware, but most often it is the result of an incorrect association of an application with the .JKS file extension.