A zombie computer, or zombie, is a computer attached to the Internet that has been compromised by a hacker, computer virus, or trojan horse. Generally, a compromised machine is only one of many in a network of remotely controlled computers used to perform malicious tasks. Most owners of zombie computers are unaware that their systems are being used in this way, but the damage caused by such systems can be devastating. Approximately what percent of the world’s spam is sent from zombie computers? Discuss