tris buffer ph=8.5, will upvote

Tris Buffer, PH=8.5 This problem will be done for one of the two buffers you made. (Your lab partner should do these calculations for the other one.) a. What is the ratio of A/Ha in your buffer after you adjusted its pH to the required value? b. How many micromoles of Aand HA are present in the solution? c. If you now add 3mL of 1MNaOH, will you still have a valid buffer