In a time series forecasting model, the demand for five time periods was 10,13,15,18 and 22. A Linear regression fit resulted in an equation
F = 6.9 + 2.9 t where F is the forecast for period. The sum of absolute deviations for the five data is
(a) 2.2 (b) 0.2 (c) –1.2 (d) 24.3