Is it possible for a couple entering a second marriage to sign a prenuptial agreement to prevent comingling of asets and for the husband to renounce his right to inherit his wife' assets?

Sources can be found here 

What are vows? Are they a good tool in avodas Hashem? What can be done to avoid becoming bound by vows?

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Is it permitted to play music for young children durng the Three Weeks?

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If one mistakenly purchased dog food that contains basar b'cholov (meat and milk cooked together) is it permitted to return the dog food to the store for a refund?

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Is it permitted to swim on Shabbos?

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