C. A box plot is best for displaying the spread of data above and below the median, so Yuki should use a box plot.
Step-by-step explanation:
Neither dot plot nor histogram shows the median of data, but box plot it does. Also, box plots show the how spread data is from minimum value to first quartile, from first quartile to median, from median to third quartile and from third quartile to maximum value.
The answer is B. because if you make an equation in the form y=mx+b then you can solve the equation by inputting x where x goes in the equation and solving. BTW the equation would be y=2x-1