**1. Find Z so that P(-z<Z<z)=0.3108**

(I know that the bell shaped graph has the 0 mean in the middle, with a Z falling on each side... and I know the 0.3108 is the area between these 2 z's and that I have to work backwards to find them, I just can't figure out how to get started)

**2. If X has a normal distribution with mean 65 and standard deviation σ, what is P(X<65)?**

(I know this is finding the area/probability of the space that is less than the average of 65... again, just can't get started. One of the options is "cannot be determined from information given", so that could be it...)

Thank you in advance!