TASK DEFINITION: In this task, you need to translate the given English sentence to Polish language.
PROBLEM: is sometimes called the marginal cost. 

SOLUTION: nazywamy go niekiedy kosztem krańcowym. 

PROBLEM: let me draw that a little bit more centered, negative five

SOLUTION: pozwólcie, że nieco wyśrodkuję, minus pięć.

PROBLEM: in the virus world. 

SOLUTION:
w świecie wirusów.