Please solve all of it

Which of the following are used in an electrochemical cell? a. electrodes b. electrolyte c. terminals d. all of the above

The brightest star in the night sky in the northern hemisphere is sirius. its distance from earth is estimated to be 8.7 light years. a light year is the distance light travels in one year. light travels at a speed of 3.00 × 108 m/s. calculate the distance from earth to sirius in miles. (1 mi = 5280 ft) g

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