Answer
a)423
b)0.866< p < 0.934
c)0.883 < p < 0.917
d) The 99% confidence interval.
Work Step by Step
a) $x=514⋅0.9=426.6≈423.$
b)0.866< p < 0.934
c)0.883 < p < 0.917
d) The 99% confidence interval is wider because it has a bigger confidence interval and hence is less precise.