Electromagnetic waves with low frequencies have been used for long-distance underwater communication. these waves most likely belong to which of the following parts of the electromagnetic spectrum?
a. gamma rays
b. infrared waves
c. radio waves
d. x-rays

Which statement best describes how private industry decides where to spend the money on research and development

Explain the difference between each pair of concepts. a. frequency and relative frequency b. percentage and relative frequency a. select the correct choice below. a. frequency is the total number of observations in a data set. relative frequency is the number of times a particular distinct value occurs. b. frequency is the number of times a particular distinct value occurs. relative frequency is the ratio of the frequency of a value to the total number of observations. c. frequency is the total number of observations in a data set. relative frequency is the ratio of the number of times a particular distinct value occurs to the frequency. d. frequency is the number of times a particular distinct value occurs. relative frequency is the ratio of the frequency of two different values.

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