firewalls include personal firewall software and firewall software on servers. Such firewalls can be used alone or as part of an in-depth firewall deployment.

look at the engine block shown in the figure. the engine shown in this figure is a/an  

  a. four-cylinder, horizontally opposed engine.

  b. eight-cylinder, v-type engine.

  c. six-cylinder, v-type engine.

  d. four-cylinder, in-line engine