Based on the box-and-whisker plot shown below, match each term with the correct value.

median
a0
range
a1
25th percentile
a2
75th percentile
a3
inter-quartile range
a4

Box plot allows us to determine the mean, the largest or the lowest number in the data set as well as the quartiles in the data. In this case, from the given figure, median is equal to 18, the range is equal to 21-15 equal to 6. The 25th percentile is equal to17 while the 75th is equal to 20. IQR then is equal to 20-17 equal to 3. 

It is the top one. the answer is -7. that is smallest