Which of the following can be determined from a box-and-whisker plot?
mode
median
mean
average

Median can be determined from a box and whisker plot

Median is the answer

Explanation  :

Box  and whisker plot

In box  and whisker plot ,  the left end point is minimum value of data

right end point is the  maximum value of all the data

The left end of box is the 25% quartile mark and right end of box is 75% quartile mark . The middle line in the box is the 50% quartile mark.

The middle line is the median of the given data.

Box  and whisker plot can be used to determine minimum , maximum and median , interquartile range of the given data

so, median can be determined from a box and whisker plot

Lean more :  link

The middle vertical line inside the box is the median or the value of Q2. The term "median" is used more often instead of Q2, but your book may use this terminology as well.

side notes:

* The left and right edges of the box are Q1 and Q3 respectively

* The IQR (interquartile range) is found by subtracting Q3 and Q1

* The min and max are the left and right most edges of the the whiskers, this is assuming there are no outliers

* There is no way to get the mean or mode from a box and whisker plot alone.

* The term "average" is too vague and could refer to mean, median, or mode.