If your score on your next statistics test is converted to a z? score, which of these z scores would you? prefer: minus? ? 2.00, minus? ? 1.00, ? 0, 1.00,? 2.00? why?

The 2.00 because the standard deviation 2.00 is directly above the mean and correspond to highest of five different likely test scores. A z score or the standard value is the number of standard deviations that a given value x is above or below the mean. A negative z score corresponds to an x value less than the mean. A positive z score corresponds to an x value greater than the mean. The more negative the z score the further the x value is below the mean. The more positive the z score the further the x value is above the mean. 

the 8 in 8,420 is in the thousands place so it's value is 8 thousand.

the 8 in 6,870 is in the hundreds place so it's value is 8 hundred.

divide 8000 by 800 to find the answer:

8000 / 800 = 10

the 8 in 8,420 is 10 times greater than the 8 in 6,870