The following is the quarterly sales for a firm for 4 years. Can we check if there is a seasonal effect? (1 point) Year Quarter 1983 2 3 4 1984 2 3 4 Sales ($'000) $ 4,190 $ 4,927 $ 6,843 $ 6,912 $ 4,521 5,522 $ 5,350 $ 7,204 $ 4,902 $ 5,912 $ 5,972 $ 7,987 $ 5,458 $ 6,359 $ 6,501 $ 8,607 1985 2 3 4 1986 1 2 3 4