What was the primary reason for these masks during world war i?

president thomas jefferson commissioned the expedition shortly after the louisiana purchase in 1803 to explore and to map the newly acquired territory, to find a practical route across the western half of the continent, and to establish an american presence in this territory before britain and other european powers

freedom of speech is also protected by the 1 amendment.

explanation:

here is pretty much what the 1st amendment says:

congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.

) the chinese armed forces had been removed from the city