Which statement best describes the principle of the camera obscura?
a: light passing through a hole in the wall of a completely darkened room forms an image of the outside object on the opposite wall.
b: light passing through a hole in the wall of a completely darkened room forms an inverted image of the outside object on the opposite wall.
c: light entering a room will form an image of whatever lies outside on the opposite wall of the room.

Read the excerpt from the building of manhattan. the heater cranked the blower handle to force air up through the fire and heat the rivets in the furiously burning bed of coals. he knew how hot the rivets were by the way their color changed. cherry-red rivets were 1,000 to 1,950 degrees fahrenheit. at the right moment he grabbed one in his tongs and tossed it to the catcher. which phrase cannot be changed in a paraphrase of this text? “the furiously burning bed of coals” “by the way their color changed” “1,000 to 1,950 degrees fahrenheit” “force air up through the fire and heat”