Answer
E = 0.088
$\hat{p} = 0.175$
Work Step by Step
Lower Bound: 0.087, Upper Bound: 0.263,
i) Find Error
Width of Interval = Upper Bound - Lower Bound
(0.263 - 0.087) = $\hat{p} + E - (\hat{p} - E)$
0.176 = 2E
E = 0.088
ii) Find $\hat{p}$
$\hat{p} - E = Lower Bound$
$\hat{p} = Lower Bound + E$
$\hat{p} = 0.087 + 0.088$
$\hat{p} = 0.175$