The ionosphere reflects

a. microwaves. b. AM radio waves.
c. FM radio waves. d. x-rays.


b

Physics & Space Science

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Identify a true statement about carbonaceous chondrites

A) They contain significant amounts of hydrogen. B) They have not changed since they formed. C) They are mostly composed of nonvolatile compounds. D) They do not provide information about the early Solar System.

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When the measured quantity 45.67 kg is divided by the measured quantity 3.42 L, the answer should have how many significant figures?

a. Three b. One c. Four d. Two

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Since the big bang, but before now, a time existed where matter was not dominant

a. True b. False Indicate whether the statement is true or false

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In a circuit made up of inductor L, resistor R, ammeter, battery, and switch in series, the current is greatest at which of the following times, as measured after the switch is closed?

a. ten time constants c. one time constant b. at a time t = L/R d. zero

Physics & Space Science