What is the context of this?
This would be the atomic mass. Hope this helps!! :)
<span>The stars change position in the sky through the course of the night just like the sun changes position in the sky through the course of a day, they rise in the east and set in the west. If you were to start watching a star in the east at the beginning of the night and keep observing that same star for hours, you will see the star's position move across the sky and eventually drop below the western horizon. There some stars that don't rise and set through the night though. The stars near the celestial pole move in circles around the pole. There is one star in the sky that doesn't appear to move at all, because it is located in line with the Earth's axis of rotation, or in other words, on the celestial pole. This star is Polaris, or more commonly known as the North Star. The south celestial pole currently lacks a star so there is no southern hemisphere counterpart. In reality, Polaris isn't perfectly on the celestial pole so even it moves in a very small circle too small to be seen with the naked eye.</span>
President pro tempore is your answer
The meaning of the above phrase is "temporary president", and is the acting president when the president & vice president is not available.
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