What can geologist infer from the rounded and eroded shapes of the appalachian mountain
a. the principle of uniformitarianism does not apply
b. the mountain formed recently
c. the mountains are made out of soft rocks
d. the mountains have been eroding for millions of years

Sally turns on her cellular telephone to speak to her friend who is located thousands of miles away. which of the following best describes how such a telephone is able to transmit and receive information? a. the cellular telephone transmits, receives, and encodes information using only sound waves. b. the cellular telephone transmits, receives, and encodes information using only electromagnetic waves. c. the cellular telephone transmits information by electromagnetic waves to a receiver which then encodes them and produces sound. d. the cellular telephone transmits information by sound waves to a receiver which then encodes them and produces electromagnetic waves.