Which group of numbers is missing from this number pattern? 8,10,12

Why would someone who is studying the history or culture of this time. find this text interesting important or useful?

Which of the following most likely contributed to the outbreak of world war ii? a. embargoes on international trade b. higher tariff rates in european countries c. sanctions imposed by the united states d. global economic depression

What prompted president monroe and secretary of state adams to issue the monroe doctrine?