Answer:
a) Sample size = 822
b) Margin of error = 0.03407
Step-by-step explanation:
We are given the following in the question:
p = 74% = 0.74
a) Sample size is required to obtain margin of error of 0.03
Formula:


Putting values, we get,

Thus, the sample size must be approximately 822 to obtain a 95% confidence interval with an approximate margin of error of 0.03
b) Margin of error for the 95% confidence interval
p = 54% = 0.54
Formula:


Putting values, we get,

The margin of error now will be 0.03407.
2/3 x 1/5 = 2/15 that is the answer