How do the viruses propagate between computers?

What is social engineering?

How will an SPI firewall handle a packet containing a TCP segment which is an acknowledgement?

For each of the following passwords, first state the kind of attack that would be necessary to crack it. Justify your answer. Then say whether or not it is an adequate password, again giving specific reasons.

password

Winter1

SpringBreaK

2!T*d

9g&8tY7#?s+445=232+