$[6$ pts$]$ For an A$/$D converter with Vref $=3\mathrm{.}3$ volts and $(1)/(2)$ LSB error, please answer the

following questions.

$($a$)$ How many bits does the converter require to have a $($quantization$)$ error of less then $0\mathrm{.}25$

mV$?$ Please show how you arrived at the answer.