You bought a regular house which current value is 500,000. If the value of the house grows according to the formula V= 500,000 x (0.9t +1)^1/3. The interest rate is 5% per year semi-annually compounded. t stands for time and is measured in years. Time is set to zero at the present time.

1. When is the optimal time to sell the house?
2. Compute its optimal selling value