Glaciers advanced from Canada and retreated four or more times. Over a few million years, Puget Sound was carved and scoured by glaciers. Heavy Pressure. Glaciers containing up to 2,383 cubic miles of ice pushed over the Puget lowland.
AM stands for amplitude modulation, while FM stands for frequency modulation. In AM, the amplitude (the height or depth of the crests or troughs) changes, while in FM, the fre â¦ quency changes. Answered.
The second advantage that FM radio has is its use of a higher frequency range. AM radio operates from 535 kHz to 1605 kHz. When you tune the dial on your radio, the number changes by 10 kHz each time. This means that each station has 10 kHz of bandwidth on which to broadcast.