Careful measurements reveal that a star maintains a steady apparent brightness at most times, except that at precise intervals of 73 hours the star becomes dimmer for about 2 hours. The most likely explanation is that:.1. The star is cepheid variable.2. The star is a member of binary eclipsing star system.3. The star is peridically ejecting gas into space every 73 hours.4. The star is a white dwarf.

2. The star is a member of binary eclipsing star system.

Explanation:

The question above shows an example of an eclipsing binary star. This type of star is very variable because the intensity of its brightness varies in the deccore of a few hours. This is because these stars are so close to an observer's field of view on the Earth's surface that they are easily eclipsed, and it is exactly these eclipses that cause the brightness of these stars to vary, which undergo a constant period of approximately 73 hours. intense shine, followed by constant drops in the intensity of that shine (lasts about 2 hours).

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