Zhang Shan Cai is a researcher in Taiwan. She wants to know if there is any difference in the average hours spent on reading each day for people aged 21 to 30 years, 31 to 40 years, and 41 to 50 years. Shan Cai conducted a survey by randomly recording 15 adults’ reading time for the three groups. From the data collected, she determines that the sum of squares reading time between the groups is 568.94 and the sum of squares reading time within a group is 187.67. 

a. Prepare the complete analysis variance table.
b. Test the null hypothesis of equality of the three population mean average hours spent on reading each day.