To answer 1.) In KJB Daniel 9:27 "and from an overspreading of abominations he shall make it desolate". In KJB Daniel 9:26, "desolations are determined".
Abomination
s, not just one abomination.
Desolations, not just one desolation.
The first of the abominations that made desolate Jerusalem was the first roman jewish war that saw the killing of perhaps a million jews and the destruction of their temple.
another Abomination that made desolate Jerusalem and its holy mount was
Aelia which came from Emperor Hadrian's
nomen gentile,
Aelius, while
Capitolina meant that the new city was dedicated to
Jupiter Capitolinus, to whom
a temple was built on the
Temple Mount.
Another Abomination that made desolate jerusalem and its holy mount was
Dome of the Rock, Arabic
Qubbat al-Ṣakhrah, shrine in
Jerusalem built by the
Umayyad caliph
ʿAbd al-Malik ibn Marwān in the late 7th century CE. It is the oldest
extant Islamic monument. The rock over which the shrine was built is sacred to both Muslims and Jews. Although it is not a mosque, it is the first major Muslim monument for public worship.
Another abomination that made desolate jersusalem was the Siege of Jerusalum 1099. The siege is notable for the mass slaughter of
Muslims and
Jews perpetrated by the
Christian crusaders,
Desolations have been decreed and have occurred. Perhaps though more desolations are to come.