Hello i need the answer as soon as possible please:

Use the below cumulative frequency graph to determine if the data is normally distributed or not. Explain your reasoning????????

please give me correct answer and in X-axis why put the classes not the upper class boundary ?

d Ogive Graph - Cumulative Frequency Polygon 20 18 16 14 12 10 NAO. OOC 4.2-4.32 4.33-4.45 4.46-4.58 4.59-4.71 4.72-4.84 X