Assume that returns are normally distributed with mean alpha and variance sigma^2. In estimating these parameters from market data, what can be said to be true? Observing data at shorter time intervals will improve the accuracy estimate of sigma^2 but have no effect on the accuracy of the estimate of alpha Observing data at shorter time intervals will improve the accuracy estimate of both sigma^2 and alpha Observing data at shorter time intervals have no effect on the accuracy of the esimate of the accuracy estimate of both sigma^2 and alpha