Final answer:
The question involves statistics methods, such as sampling adequacy and confidence interval calculations, within the Mathematics field at the College level.
Step-by-step explanation:
The student's question pertains to the field of statistics, which falls under Mathematics. It involves evaluating the adequacy of a sample size, the representation of a sample to a population, and computing confidence intervals for a proportion. For instance, to compute a 90% confidence interval for the true percentage of students against new legislation, one would use the sample proportion and apply the formula for confidence intervals. Regarding the survey of 3,274 individuals born since 1971, the sample size seems large enough, but the representativeness may depend on the survey methods. Confidence intervals provide an estimated range where the true proportion is expected to lie, offering a more precise understanding than a gut feeling alone.