Evaluate the following expression, where r = 3 and s = 8:

12r - s

a
44
b
28
c
4
d
5

The expression is:

12r - s

Substitute r = 3 and s = 8:

12(3) - 8
= 36 - 8
= 28

So, the value of the expression is 28. Therefore, the correct option is: b) 28