Test of Significance

#1
I'm having trouble finding the P-Value and the Test of Significance: Zcrit and Ztest. This is data for pH values for electrode and optical)

here is what I have

the hypothesis is

H0: µe = µo
Ha: µe ≠ µo


(e= electrode and o = optical)

o = 0.035
e = 0.021


here is all my work

http://www.imagedump.com/pics/521046.gif

untill i can upload the stuff to a better site. just copy the link and paste it in browser.
Z= (Xbar -µ)/(ờo)
Z= (Xbar -µ)/(ờe)