Hello!
The answer is:
The fourth option,
{s | s <90}
Why?
Solving inequalities involves almost the same process of solving equalities for variable isolation.
We are given the inequality:
![\frac{1}{3}s-6](/tpl/images/0026/1660/7ba64.png)
So, solving we have:
![\frac{1}{3}s-6](/tpl/images/0026/1660/bf69b.png)
Hence, we have that the correct option is the fourth option:
{s | s <90}
Have a nice day!