The Brownian Motion is used to model the liquid assets $($i$.$e$.$ "cash"$)$ of our startup company Math Finance Inc. Yo our company's CFO $($Chief Financial Officer$).$ The initial value of our assets is $5($measured in tens of thousands of dollars$).$ The drift and volatility for the first two years turns out to be $2$ and $3$ respectively. During the next two yea the drift and volatility was observed to be $3$ and $4$ respectively. What can you say about the probabilistic behavior our assets at the end of year four? Give proper mathematic explanation. What is the probability that our assets wil worth at least $$150,000?$