There are $3+5+1=9$ students in each row, and there are $2+1+1=4$ rows. Thus, there are $9\times4=36$ students in this class. 
The students in a class sit in rows. There is the same number of students in each row. There are $2$ rows of students in front of Robert and $1$ row of students behind him. In his row, there are $3$ students on his left and $5$ students on his right. How many students are there in this class? (2022 Math Kangaroo Problem, Level 3-4, Question \#15) 

a) $$10$$ 
b) $$17$$ 
c) $$18$$ 
d) $$27$$ 
e) $$36$$ 