Why would a researcher use a secondary source instead of a primary source when analyzing a historical event?

Which of these works from the italian renaissance exhibits contrapposto?

How did the catholic church change as a result of the council of trent? a. catholic printers were encouraged to publish translations of the bible in common languages b. members of the catholic clergy were required to avoid luxurious lifestyles c. catholics were told they could earn salvation through god’s grace alone d. european catholics were barred from initiating any conflict with protestants.

Plz which of the following elements is not typical of an advanced society. a. cities b. science c. industries d. a nomadic lifestyle