1 1/16 is it's simplest form.
Total pay before deductions is gross pay <==
total pay after deductions is net pay
If you added more context then I would probably answer your question
3 sodas cost $2.97 +.15 tax total $3.12
A function is positive if it lies above the x axis.
This function is positive before x = -4, i.e. over the interval 
It is negative elsewhere, i.e. over the interval 
So, the only correct option is the second one.