The marks of Riju in Mathematics test increased from 20 to 30. What is the percentage of increase?

The box plots show the distributions of the numbers of words per line in an essay printed in two different fonts.which measure of center would be best to compare the data sets? the median is the best measure because both distributions are left-skewed.the mean is the best measure because both distributions are left-skewed.the median is the best measure because both distributions are symmetric.the mean is the best measure because both distributions are symmetric