An electrical contractor's records during the last five weeks indicate the number of job requests: Week 1 2 3 4 5 Requests 20 22 18 21 22. Predict the number of requests for Week 6 using each of these methods: (a). Naive. (b). A four-period moving average. (c). weighted moving average using 0.50 for week 5, 0.30 for week 4, and 0.20 for week 3. (D). Exponential smoothing with alpha=.30. use 20 for week 2 forecast.