A dwarf star has the longest life.
Isotopes have same atomic number but different atomic mass number.
Hence option B is correct.
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The three beams on a triple beam balance all are different. Each beam should have a differnet unit of measurement. For example, one beam may count in 100's and the other beam may count in 10's and the last beam may count in 1's.
Answer:

Explanation:
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In this case, the undergoing chemical reaction is:

In such a way, considering the 3 to 1 molar relationship between ammonia and ammonium phosphate, the moles of ammonia result:

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