19. Kirsten has a device that has an electromagnet at its core. It is surrounded by a permanent magnet. She can attach the device to a battery and it will spin. What type of
device does Kirsten MOST LIKELY have?
a. a solenoid
b. a simple motor
c. an electromagnet
d. a simple generator

8. why do radio telescopes convert radio waves (analog signals) to electrical (digital) signals for analysis? (hint: what did the article say about the advantages of digital signals? )

Which of the following correctly describes the early view of catastrophism?

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.