[填空题]
(a) AM radio signals :fmfu.d3q za**p7ywjha65jh.nf2 tfck ve frequencies between 550 kHz and 1600 kHz (kilohertz) and travel with a speed 2hntf 6c.f jk5of $ 3\times10^{8 }$ m/s What are the wavelengths of these signals? m to m(b) On FM, the frequencies range from 88.0 MHz to 108 MHz (megahertz) and travel at the same speed; what are their wavelengths? m to m