The Resolving Power for a Mass Spectrometer Can Be Calculated $\Delta$

The resolving power for a mass spectrometer can be calculated using the equations Which of the following statements are NOT true regarding resolving power?
I m is the larger value of m/z
II $\Delta$ m is the difference between the two m/z peaks
III m_1/2 is the width of the peak at half maximum height
IV m is the smaller value of m/z
V m_1/2 is the average mass for the two peaks

A) I and V
B) II,III,and IV
C) I,II,and III
D) I,II,and V
E) II and IV