Q3 Part (a) and (b)

library(astsa) then you can use both salt and saltemp

- . . . . . . . . . .. . . . . . . . . . . . .. .. 10 . . . . . . 8 temperature 6 4 30 20 20 cols . . .. . . . . . 40 10 rows 60 Fig. 1.18. Two-dimensional time series of temperature measurements taken on a rectangular field (64 X 36 with 17-foot spacing). Data are from Bazza et al. [15]Average Temperature 5.5 6.0 6.5 7.0 7.5 0 10 20 30 40 50 60 row Fig. 1.19. Row averages of the two-dimensional soil temperature profile. As],. = Es, Xsi,$2/36Q3. The levels of salt concentration known to have occurred over rows, corresponding to the average temperature levels for the soil science data considered in Figs. 1.18 and 1.19, are in salt and saltemp. library(astsa); data(salt); data(saltemp). a. Identify the first three dominant frequencies by performing separate spectral analyses on the two series. b. Include 95% condence intervals for the dominant frequencies in part(a) and interpret your ndings