How is “twelve men” formed in the nominative?

Number Nouns: Rules from One to One Thousand

• اثْنَيْ عَشَرَ رَجُلًا
• اثْنَتَا عَشْرَةَ رَجُلًا
• اثْنَا عَشَرَ رَجُلًا
• اثْنَا عَشَرَ رِجَالٍ