Tarleton State University grants credit for IB higher level exams with a score of 5 or higher and for some standard level exams with specified scores of 5 or higher. A list of credit equivalents and required scores is on the testing site for certain higher level and standard level exams.
Per stirpes distribution or right of representation refers to children/child of the decedent, or their heirs. If the child that was an heir passed away before the parent but they left behind a child/children then that child/children will inherit in the place of the parent that died before the grandparent.
A spouse inheriting a traditional IRA has similar options, with slightly different rules. You can withdraw all the money at once, though you'll pay taxes on the sum at your ordinary income rate -- which might be extra high because of the extra income from the inheritance.