Why is arsenic called “a silent killer”?

In edgar allen poe's "masque of the red death", what object is kept in the black room?

Drag the tiles to the boxes to form correct pairs. david sedaris's essay "our perfect summer" appeared in the june 16, 2003, issue of the new yorker. match each element of sedaris's essay to an element of a narrative essay. tiles time setting plot geographical setting conflict characters pairs the writer and his mother had always talked about the family buying a second home like the rich people they knew. the writer grew up in raleigh, north carolina, and his emerald isle in the summers.

Which of these events inspired many of stephen crane’s writings, including the story “an episode of war”?