1. One of the critical regions is $X\geq20$.  You are given the following probabilities:

$P(X\leq8)=0.04603$

$P(X\leq9)=0.08932$

$\text{P}(X\leq10)=0.15526$

Given that a 10% level of significance is used, determine the other critical region. Give a reason for your answer by using a relevant probability.