CRISPR Cas9, Inc which makes Protein for Gene therapy has received complaints of inconsistent quantities in its packaging. Packed correctly, the...

1.       What is the p-Value? Should we reject the Null?  

We have to manually calculate this using a standard Z table. I calculated the p value as .0459. Professor says the real answer is .0455003

Help me understand wrong answer.

Also, this should be a 1 tail correct?