Diaries, letters, and memoirs are good examples of what kind of source?

Technician a says that the sine with dwell (swd) test is used to determine if an electronic stability control system functions normally. technician b says that the esc lamp, called a telltale light, is required to remain on for two minutes. who is correct?

This law states that the "chinese laborers to this country endanger the good order of certain localities" in the united states. which of these would represent a "locality" that would most likely have wanted this law created and passed? a) dallas b) chicago c) atlanta d) san francisco

What was the land like around rome? dry rocky fertile volcanic