Which of the following are examples of passive attacks?

		An attacker uses a ping command to check if a target's network device is up.
		An attacker is able to attach a network tap between devices in the target's network, allowing the network traffic to flow freely but copying the packets to the attacker's monitoring device.
		An attacker uses a sniffing tool to watch the target's network traffic for packets of interest.
		An attacker uses a botnet of infected computers to make repeated HTTP requests to the target's web server.