a) They give you the hydronium ion concentration - it's there in brackets (0.01mol/L). Assuming the HCL is completely ionised, then it's [H+] conc. is equal to 0.01mol/L. Therefore, pH = 10^-0.01
b) Sulphuric acid is diprotic, HCL is monoprotic - you need multiply the [H+] concentration of...