Question 1: 100%
statistically 60% should pass, which means it's 100% LIKELY that 60 will pass.
Question 2:
with a standard deviation of 3 it'll most likely be between -3 and +3 deviation from 300ml.
With 6 bottles you ought to end up with -1, +1, -2, +2, -3, +3
2 of them will end up being lower than 299 (298 and 297ml)
your chances of hitting one of these 2 bottles when going through them is 2/6 = 1/3. so 33.33%
riiiiiiight?