A buffer solution is prepared by mixing 10 ml of 1.0 M acetic acid & 20 ml of 0.5 M sodium acetate and then diluted to 100 ml with distilled water. If the pKa of CH3COOH is 4.76. What is the pH of the buffer solution prepared?
(a). 3.84
(b). 4.76
(c). 4.34
(d). 5.21