6. 1-7, 8-14, 15-21, 22-28 are the classes, the size of the class is
a. 6
b. 7
c. 8
d. 9


8. If the mean of 6, 8, 5, 7, x and 4 is 7 then what is the value of x?
a. 8
b. 10
c. 12
d. 14


10. What is the mode for the data in item number 7?
a. 0
b. 3
c. 7
d. 8 ​