You are considering buying three stocks whose prices at time t are given t are given tby P$1$std$,$P$2$std$,$ and P$3$std$.$ You know that dPdPd$1$dt is a large positive number, dPdPd$2$dt is near zero, and dPdPd$3$dt is a large negative number. Which stock will you buy? Explain your answer.