I started the problem, but i'm having trouble find the z score.

a = 0.005; H 1 is p ≠ 20

H1: p ≠ 20

Since 0.005 is used, then .05 standard normal distribution
2 tails are used to find the critical value and region.

I don't no if I'm heading in the right direction of find the score for an alternative hypothesis.