How to solve this lognormal distribution problem?

1. For PR(A<=4), you can use excel function of
=NORM.DIST(4,3,SQRT(5),TRUE)
or use the normal table for the value Phi((3-4)/SQRT(5))
to get the probability of getting a value of anything up to 4 with the correspond parameters. This calculation would return 0.672, hence you are looking for the complete (to reach Pr(A>4)) 1-0.672= 0.327.

2. It's a problem if you don't have the mean and SD, basically no big difference between calculations... (use lognormal table)

Good luck!