I need help with this pleas ASAP this is over due

Noble gases are the most reactive elements on the periodic table. a. true b. false

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.