Which statement about «لَا تَأْمَنَّا» is correct?

Rules of Waqf — Correct Stopping, Resumption, Rawm, Ishmām and Qurʾānic Orthography

• It is ordinary fatḥatayn
• A special assimilation of two nūns is discussed
• It ends with tāʾ marbūṭah
• Stopping with alif is obligatory