question #1 Sahih al-Bukhari 539, Book 9, Hadith 16 : Why is it recommended to delay the Zuhr prayer during extremely hot weather?

We were with the Prophet (ﷺ) on a journey and the Mu’adh-dhin (call maker for the prayer) wanted to
pronounce the Adhan (call) for the Zuhr prayer. The Prophet (ﷺ) said, ‘Let it become cooler.” He again
(after a while) wanted to pronounce the Adhan but the Prophet (ﷺ) said to him, “Let it become cooler till
we see the shadows of hillocks.” The Prophet (ﷺ) added, “The severity of heat is from the raging of the
Hell-fire, and in very hot weather pray (Zuhr) when it becomes cooler.”