Given data:
The original cost is C=$35.
The sales tax is s=3.8%.
The final cost after sales tax is,
[tex]\begin{gathered} F=C(1+s) \\ =35(1+\frac{3.8}{100}) \\ =35(1.038) \\ =36.33 \end{gathered}[/tex]Thus, the final cost after the sales tax is $36.33.