Potassium is an alkali metal with the chemical symbol K. It has an atomic number of 19, meaning that it has 19 positively charged protons. It also contains 19 electrons, which have a negative charge, and 20 neutrons, which do not hold a charge
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Answer: heat
Other indicators: color change, odor, gas, temperature change.
Which type of telescope is most useful for detecting a star that emits very long electromagnetic waves?
A. a radio telescope B. an X-ray telescope C. an optical telescope D. a gamma ray telescope
A.)a radio telescope
