What binary coding is used most often for e-mail purposes?

In the midst of a cybercrime investigation, a key witness has suddenly become unavailable due to a serious illness. According to Federal Rule 804, which exception to the rule against hearsay allows for introducing this witness's previous testimony at a different trial in a current proceeding?

During an ongoing cybercrime investigation, a non-expert witness, who is an employee of the organization, testifies to observing unusual computer activity. Simultaneously, an expert witness introduces a record of the regularly conducted activity of the organization. The record was kept near the incident's time adept as part of the regular activity. It reveals a similar observation as the non-expert witness. How would the Federal Rules of Evidence classify and treat these testimonies in this scenario?

What does the Rule 101 of Federal Rules of Evidence states?

Which of the following application password cracking tool can discover all password-protected items on a computer and decrypts them?