The $pH$ of blood is maintained constant by the mechanism of:

The $pK_a$ of a weak acid is $4.8$. What should be the ratio of $\frac{[\text{acid}]}{[\text{salt}]}$, if a buffer of $pH = 5.8$ is required?

The addition of small amounts of either acid or base to a buffer solution causes only small changes in $pH$ because the buffer solution

The $pH$ of blood does not appreciably change by a small addition of acid or a base because blood

$50 \ mL$ of $0.02 \ M$ $NaOH$ solution is mixed with $50 \ mL$ of $0.06 \ M$ acetic acid solution. The $pH$ of the resulting solution is $......$ ($pK_a$ of acetic acid is $4.76$,$\log 2 = 0.30$).

$0.1 \, M$ acetic acid solution is titrated against $0.1 \, M \, NaOH$ solution. What would be the difference in $pH$ between $1/4$ and $3/4$ stages of neutralization of acid?