Consider a series that follows an MA(1) with zero mean and a moving average coefficient of 0.4. What is the value of the autocovariance at lag 1?
a. .4
b. 1
c. .34
d. It is not possible to determine the value of the autocovariances without knowing the dis

d. It is not possible to determine the value of the autocovariances without knowing the disturbance variance because the autocovariance is a function of the variance of the disturbances. The autocovariance is defined as the expected value of the product of the disturbances at two different lags. Therefore, in order to calculate the autocovariance at lag 1, the variance of the disturbances must be known.