The frequency table shows the marks scored by 32 students in a test.

Marks scored	1	2	3	4	5	6	7	8	9	10
Number of students	2	3	4	4	4	4	5	3	2	1

a(i) Find the mean of the marks

(ii) Find the median of the marks

(iii) Find the mode of the marks

b.  Percentage of those who scored at least 8 marks