What causes madd in «وَلَا أَنْتُمْ»?

Al-Kāfirūn and An-Naṣr: Applied Madd, Idghām, Ghunnah and Waqf

• Hamzah in the same word after alif
• Alif madd then hamzah in the next word
• Sākin nūn before tāʾ
• Mīm before ʿayn