Dry soil is characterized by  εr  = 2.5,µr  = 1, and  σ  = 10‑4  (s/m). at each of the following frequencies, determine if dry soil may be considered a good conductor, a quasi-conductor, or a low-loss dielectric, and then calculate  a. β,λ,µp>   and  ηc:
(a) 60 hz
(b) 1 khz
(c) 1 mhz
(d) 1 ghz