Scientists often repeat experiments multiple times. why is this important?

In the years following world war 1 , the red scare played a key role in the following political changes except

You should consider using floor dry compounds or hydrophobic mops if a spill is bigger than what can be wiped up with shop rags. a) one b) two c) three d) four

What would a student most likely use if he or she wanted to consult a secondary source