When you get a vaccine it injects a controlled amount of the illness into you, so the immune system can build up an immunity. The memory cells come into play when the illness comes back.
Answer:
Guilds: they are medieval association of workers and craftsmen which ensure mutual aid and quality work in a particular production process in which they hold a monopoly acquired from the state.
During the mid-eighteenth century, they became the center of criticism by the followers of free trade who believed that restriction of work by the sate should be ended for a more competitive economic structure. By the mid-nineteenth century, the monopoly of guilds seemed to be disappeared.
The best definition of "civic virtue" from the list would be "<span>behavior skills and habits of citizens that are constructive to democracies" although these trais are helpful in building any society. </span>
Answer:
Slavery and plantations.
Explanation:
There was an enormous need for labor to pick cotton and slaves were free labor.