Hi,
The hypothesis test produces a z= -2.60 ⇒ reject Ho
a a/2 crtical regions
80% 0.2 10% z <-1.28155 z >+1.28155
90% 0.1 5% z <-1.645 z >+1.645
92% 0.8 4% z <-1.751 z >+1.751
95% 0.05 2.50% z <-1.96 z >+1.96
98% 0.02 1% z <-2.326 z >+2.326
99% 0.01 0.50% z<-2.576 z >+2.576