Surah 18: Contradictions

1. Have some of the verses in the Quran been abrogated? 18:27
2. Is each person free to believe (or disbelieve) whatever he or she wishes? 18:29
3. What were humans created from? 18:37
4. Is Iblis an angel or a jinn? 18:50
5. Who sends disbelievers astray? 18:55
6. Does Allah lead people astray? 18:55, 57