You can realize that sulfuric acid (H2SO4) is a strong acid because it can dissociate completely in an aqueous solution, so we can assume that the concentration [H3O+] is 0.0084 M.
We can find [OH-], using the following formula:
![\lbrack H_3O^+\rbrack\lbrack OH^-\rbrack=10^(-14).](https://img.qammunity.org/2023/formulas/chemistry/college/3r7yqwnlmfmda2aka9efsbtjs9q4yioz1h.png)
So, let's clear [OH-] and replace the data that we have:
![\begin{gathered} \lbrack OH^-\rbrack=(10^(-14))/(\lbrack H_3O^+\rbrack), \\ \lbrack OH^-\rbrack=(10^(-14))/(0.0084), \\ \lbrack OH^-\rbrack=1.190\cdot10^(-12)M\approx1.2\cdot10^(-12)M. \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/college/4vx0flh1or366erh3nrfig9agho6x5fc4h.png)
The answer is that we have 0.0084 M of [H3O+] and 1.2 x 10^(-12) M of [OH-].