2008 TIA exam 2 question

Can you give me some help with this?

A stock follows the following Ito's process

dS = .17S dS + .4 S dZ

What is the probability that the stock falls more than 10% in a given year?


I'm thinking this is a lognormal distribution but I am unsure of the mean and how to continue


2008 TIA exam 2 question