a√2
b 2
c √10
d 4
add up all of the value
13.3+14.3+15.3+16.3+17.3=76.5
then divide by 5 as there are n=5 in the set given
76.5\5=15.3
the mean of this data set is 15.3
subtract the mean from each value to get this list of differences
x1-mean=13.3-15.3=-2
x2-mean=14.3-15.3=-1
x3-mean=15.3-15.3=-0
x4-mean=16.3-15.3=1
x4-mean=17.3-15.3=2