If (x-10) is a factor of f(x), which of the following must be true? (50 points) A. Neither x= -10 or x=10 are roots of f(x)
B. f(-10)=0
C. f(10)=0
D. Both x=10 and x=-10 are roots of f(x)

Dana wants to identify the favorite professional baseball team of people in her community. she stands outside a local sporting goods store and asks every other person who enters, "what is your favorite professional baseball team? " will the results of her survey be valid? explain.