An investment returns for the years were 4% for year 1, 3% for year 2, 7% for year 3, and -2% for year 4.

1. What is the arithmetic mean and geometric mean of this investments returns?
2. If the year 1, year 2, and year 3 returns have 30%, 20% and 50% probabilities of happening, what is the expected return of this investment for the three years
3. What is the standard deviation for the investments returns in the first three years?